These not-too-sweet mini desserts combine the flavors of peanut butter cups and chocolate cake. Quinoa flour adds protein and makes these gluten-free, but feel free to substitute white whole-wheat flour instead.
Preheat oven to 350°F. Coat a 24-cup mini muffin tin with cooking spray.
Beat peanut butter and butter in a large bowl with an electric mixer until creamy. Beat in eggs, brown sugar and vanilla. Whisk quinoa (or whole-wheat) flour, cocoa, baking soda and salt in a small bowl. Mix the dry ingredients into the wet ingredients until just combined. Divide the batter among the prepared mini muffin cups and sprinkle the tops with chocolate chips.
Bake until a toothpick inserted in the center of a brownie comes out with just a few moist crumbs attached, 14 to 16 minutes. Let cool completely before storing, about 1 hour.
To make ahead: Store in an airtight container at room temperature for up to 5 days.
Equipment: 24-cup mini muffin tin