Protein Peanut Butter Cups

Ingredient Notes

(For the full recipe, scroll down to the recipe card below)

• Oat flour: You can use store-bought oat flour or make your own by blending old-fashioned or quick oats in a high-powered blender until they reach a fine, flour-like consistency.
• Peanut butter: Creamy, drippy peanut butter like Skippy or Jif works best for the smoothest filling and helps the cups hold together well. Natural peanut butter can be used, but the texture may be softer and a bit more crumbly.
• Protein powder: Vanilla protein powder gives these peanut butter cups a classic flavor, but chocolate protein powder is just as delicious. Since protein powders vary in absorbency, you may need to add an extra tablespoon or two of milk until the mixture comes together like a thick cookie dough. I like the vanilla protein powder from Clean Simple Eats, but if you have a different favorite brand of protein powder, go for it!
• Chocolate chips: I used dark chocolate chips, but semi-sweet or milk chocolate chips also work if you prefer a sweeter finish.
• Rice Krispies cereal: Adds the perfect crispy crunch and gives the filling that classic peanut butter cup texture. Use gluten-free crispy rice cereal if needed.

Step-by-Step Directions

(For the full recipe, scroll down to the recipe card below)

Expert Tips

• Use creamy peanut butter: Creamy peanut butter like Skippy or Jif creates the smoothest filling and helps the cups hold together best. Natural peanut butter can make the mixture softer and more crumbly.
• Choose a protein powder you enjoy: Vanilla protein powder gives these a classic peanut butter cup flavor, but chocolate protein powder is a delicious option if you want an even richer chocolate taste.
• Adjust the liquid as needed: Protein powders absorb moisture differently. If the mixture seems dry or crumbly, add milk 1 tablespoon at a time until it resembles thick cookie dough and holds together when pressed.
• For extra crunch: Feel free to increase the Rice Krispies for even more crispy texture in every bite.
• Use a silicone muffin pan: It makes removing the peanut butter cups incredibly easy. If using a metal muffin tin, be sure to line it with paper liners.
• Don’t skip the chill time: Refrigerate the cups until the chocolate is completely set before removing them from the pan. This helps them hold their shape and gives the best texture.
• Sprinkle with flaky sea salt: A pinch of flaky sea salt on top balances the sweetness and makes the chocolate and peanut butter flavors pop.

Variations / Substitutions

• Chocolate protein: Swap the vanilla protein powder for chocolate protein powder for an extra chocolatey filling.
• Use a different nut butter: Almond butter or cashew butter can be substituted for peanut butter. Just use a creamy variety for the best texture.
• Try white chocolate: Replace the dark chocolate chips with white chocolate or semi-sweet chocolate chips for a different flavor profile.
• Add mix-ins: Stir in mini chocolate chips, chopped peanuts, shredded coconut, or hemp hearts for extra texture and flavor.
• Make them gluten-free: Use certified gluten-free oat flour (or certified gluten-free oats to make your own) and gluten-free crispy rice cereal.

Storage / Freezing

• Store the protein peanut butter cups in an airtight container in the refrigerator for up to 1 week. They’re best enjoyed chilled, as the filling stays firm and the chocolate topping holds its shape.
• For longer storage, freeze them in a freezer-safe container with parchment paper between layers for up to 3 months. Let them sit at room temperature for 5–10 minutes before enjoying, or eat them straight from the freezer for a firmer, fudgier treat.