Pre-heat oven to 350 degrees. Line a muffin tin with non-stick (parchment) cupcake liners. Set aside.
Add all dry ingredients except chocolate chunks to a medium bowl and mix. Set aside.
Add brown sugar, maple syrup, vanilla extract, and melted peanut butter to a large bowl. Whisk until well combined, then add egg and almond milk and whisk until smooth.
Add pre-mixed dry ingredients to the wet ingredients and mix until just combined. Fold in chocolate chips, then spoon into cupcake liners, filling them to the top of the cupcake liner.
Bake muffins for 21-24 minutes or until a toothpick inserted into the center of a muffin comes out clean.
Store in a sealed container on the counter for 2-3 days or in the refrigerator for up to a week.
Notes
If you'd prefer to use whey instead of vegan protein powder, I'd recommend cutting the amount of almond milk in half.