High Protein Sweet Potato Brownies -Vegan

These high protein sweet potato brownies are one of those recipes I make when I want something properly chocolatey but also want it to be a little more substantial than a regular brownie. I make this on repeat for a quick snack, dessert or even to add to my breakfast.

The sweet potato does most of the work when it comes to the texture. Once mashed, it keeps the brownies soft and fudgy without needing loads of oil or butter. Then there’s cacao, tahini, dark chocolate and a little instant coffee, which makes the chocolate flavor much richer.

I also add soy protein isolate because, unlike some “protein brownie” recipes where you end up with 4 grams of protein, I wanted these to actually contribute a decent amount.

They’re vegan, easy to make, and one brownie comes out to roughly 12-13 g of protein, depending on the exact chocolate, tahini and protein powder you use.

Why Sweet Potato Works So Well in Brownies

Sweet potato is really useful in brownies because once it’s cooked and mashed, it becomes naturally creamy.

It adds moisture and some natural sweetness, which means you can get that soft brownie texture without needing the amount of butter or sugar you’d normally find in a traditional brownie.

You will still taste chocolate first. Between the cacao, dark chocolate chips, tahini and coffee, the sweet potato mostly disappears into the background.

Sweet potato brownies are already commonly made with nut or seed butter and cacao for exactly this reason: the puree gives the brownie moisture and structure while the richer ingredients bring the brownie flavor.

What Makes These Sweet Potato Brownies High in Protein?

Most of the extra protein comes from soy protein isolate, but you’re also getting some from:

• Tahini
• Rolled oats
• Soy milk
• Cacao
• Sweet potato

I use 60 g of soy protein isolate, which gives the whole batch a pretty substantial protein boost without making protein powder the bulk of the recipe.

There are other sweet potato protein brownie recipes that use a similar combination of sweet potato, oats or oat flour, protein powder and nut butter, so the combination itself works really well for this kind of bake.

Ingredients for High Protein Sweet Potato Brownies

This recipe makes 8 brownies.

Sweet potato

490 g / about 17 oz raw sweet potato

I weigh mine before cooking.

Boil or steam the sweet potato until completely tender, then drain it well before mashing.

You want it soft enough that you can get a smooth mash without any stubborn little potato chunks hiding in your brownie.

Cacao powder

50 g / about 1/2 cup

Use unsweetened cacao or cocoa powder.

This is quite a generous amount, which gives the brownies their deep chocolate flavor.

Dark chocolate chips

50 g / about 1/3 cup

I like dark chocolate here because the brownies already get some sweetness from the sweet potato.

You can use chips or chop up a dark chocolate bar.

Tahini

60 ml / 1/4 cup

Tahini adds richness, fat and a slightly nutty flavor without making the brownies taste strongly of sesame.

It also works really nicely with dark chocolate.

If you don’t have tahini, peanut butter or almond butter should work, although obviously the flavor will change.

Rolled oats

50 g / about 1/2 cup

The oats give the brownies more structure.

If you want a completely smooth brownie, you can blend the oats into oat flour first.

If you don’t mind a little more texture, leave them as they are.

Unsweetened soy milk

230 ml / just under 1 cup

Soy milk helps loosen the mixture and also contributes a little extra protein.

Different protein powders absorb liquid differently, so you may need a small splash more depending on the powder you use.

Soy protein isolate

60 g / about 2 scoops, depending on your scoop

Protein powder is one of the ingredients that can change the texture of a brownie quite dramatically, so if you substitute another type, pay attention to your batter. It should be thick, but still easy enough to spread into the baking dish.

Two ripe bananas

To add natural sweetness to the brownies! You can also choose to skip this.

Baking powder

2 teaspoons

Salt

A generous pinch

Chocolate needs salt, so please don’t leave it out.

Instant coffee

1 teaspoon

You don’t really taste coffee in the finished brownie. It simply makes the cacao and dark chocolate taste deeper. Espresso powder works too.

How to Make High Protein Sweet Potato Brownies

• Preheat your oven to 350°F / 180°C.
• Cook the sweet potato until completely soft. I usually boil mine, but steaming works as well.
• Drain it well and mash it with the bananas until smooth.
• Add the mashed sweet potato to a large mixing bowl along with the cacao powder, tahini, oats, soy milk, soy protein isolate, baking powder, salt and instant coffee.
• Mix everything together really well.
• The batter should look like thick brownie batter.
• If your protein powder absorbs a lot of liquid and the mixture feels too stiff, add a little more soy milk, one tablespoon at a time.
• Fold in most of the dark chocolate chips, keeping a few for the top.
• Transfer the batter to a greased or parchment-lined baking dish and spread it evenly.
• Sprinkle the remaining chocolate chips over the top.
• Bake for around 30 minutes.
• Your oven may need slightly more or less time, so start checking around the 25-minute mark.
• The top should look set, but the middle does not need to be completely dry.
• Once baked, remove the brownies from the oven and let them cool completely before slicing.
• This part matters.
• They become firmer and much more brownie-like as they cool.
• Slice into 8 pieces and enjoy.

Don’t Overbake Your Protein Brownies

Protein powder can make baked goods dry surprisingly quickly.

Add sweet potato to the situation and it can also be hard to judge doneness by looking at the middle, because these brownies are naturally moist.

I would rather pull them out slightly early than leave them in until they look completely dry.

They continue to set as they cool.

This is also why I really recommend resisting the temptation to cut them immediately. Warm sweet potato brownies can feel almost too soft, while the same brownie can have a much better fudgy texture after cooling.

What Should the Batter Look Like?

Think thick brownie batter rather than cake batter.

It shouldn’t pour like pancake batter, but you should be able to spread it across the pan fairly easily with a spoon or spatula.

If it’s extremely stiff, your protein powder may have absorbed more liquid than mine.

Add soy milk one tablespoon at a time until you get the right consistency.

Don’t dump another half cup in at once. It’s much easier to add liquid than explain to your brownie batter why it has become soup.

Can I Blend the Batter?

Yes! If you want the smoothest possible texture, you can blend the sweet potato, soy milk, tahini, cacao, protein powder and oats together.

I personally don’t think you need to if your sweet potato is mashed properly, but blending will give you a more uniform texture.

If you’re blending, add the chocolate chips after blending.

Can I Make These Without Protein Powder?

You can make sweet potato brownies without protein powder, but I wouldn’t simply remove the 60 g and bake the rest of the recipe unchanged.

The protein powder is part of the dry ingredient structure. You’d need to replace it with something such as additional oat flour or regular flour and potentially reduce the soy milk. At that point, you’re making a slightly different brownie recipe.

If your goal is specifically high protein sweet potato brownies, then I’d keep the protein powder.

Can I Replace the Tahini?

Yes.

The easiest replacements would be:

• Peanut butter
• Almond butter
• Cashew butter
• Sunflower seed butter

Peanut butter will give you a much more obvious chocolate-peanut butter brownie.

Almond or cashew butter will be more neutral.

Keep in mind that different nut and seed butters vary in thickness, so you may need to adjust the soy milk slightly.

High Protien Sweet Potato Brownie Variations:

Chocolate peanut butter

Replace the tahini with peanut butter.

You can also swirl a little extra peanut butter over the top before baking.

Walnut brownies

Add chopped walnuts along with the chocolate chips.

Chocolate, sweet potato and walnuts work really well together, and the walnuts add a nice contrast to the soft brownie.

Double chocolate

Increase the chocolate chips or use a mixture of dark chocolate chips and chopped chocolate.

Raspberry chocolate

Fold raspberries into the batter before baking.

Fresh or frozen both work, although frozen berries may add a little extra moisture.

Mocha brownies

If you actually want the coffee flavor to come through, increase the instant coffee slightly.

The 1 teaspoon in the original recipe is mostly there to enhance the chocolate.

How to Serve High Protein Sweet Potato Brownies

Honestly, I usually just eat one as it is.

But if you want to turn it into more of a dessert, try:

• Thick soy yogurt
• Fresh raspberries or strawberries
• Peanut butter
• Tahini
• Warm berries
• A little melted dark chocolate
• Vegan ice cream

For a higher-protein snack, serve one with unsweetened soy yogurt.

They’re also very good straight from the refrigerator if you prefer really dense, fudgy brownies.

How to Store High Protein Sweet Potato Brownies

Because these brownies contain a lot of cooked sweet potato and stay quite moist, I recommend storing them in the refrigerator.

Let them cool completely first, then transfer them to an airtight container.

They should keep well in the fridge for around 4 to 5 days.

I actually like the texture even more the next day.

Can You Freeze Sweet Potato Brownies?

Yes! Let them cool completely, slice into individual brownies, and place them in a freezer-safe container.

Put parchment paper between layers if you’re stacking them. Freeze for up to around 2 months.

You can thaw one overnight in the refrigerator or leave it at room temperature until softened.

A quick microwave after thawing also works if you want the chocolate chips slightly melty again.

High Protein Sweet Potato Brownies: Frequently Asked Questions

Do these high protein sweet potato brownies taste like sweet potato?

Not at all! You might notice a little sweetness from it, but cacao, banana, dark chocolate, tahini and coffee are much stronger flavors.

Do I weigh the sweet potato before or after cooking?

For this recipe, the 17 oz / 490 g measurement is before boiling.

That is important because the weight can change during cooking.

Can I steam the sweet potato instead of boiling it?

Yes. Steaming may actually give you a slightly more concentrated sweet potato because it doesn’t absorb as much water. Just make sure it’s completely soft before mashing.

Are these high protein sweet potato brownies gluten-free?

They can be if you use certified gluten-free oats and make sure your protein powder and other packaged ingredients are gluten-free.

Can I use oat milk instead of soy milk?

Yes! The recipe should still work, but soy milk contributes more protein.

Why are my brownies very soft after baking?

Let them cool completely first. Sweet potato brownies firm considerably as they cool. If they’re still extremely wet once completely cold, they may have needed a little longer in the oven.

Can I eat these cold?

Yes, and they’re really good that way! Refrigeration makes them denser and fudgier.