01 -
Set oven to 375°F. Line a 12-cup muffin tin with paper liners and set aside.
02 -
In a medium bowl, whisk together flour, cocoa powder, baking powder, baking soda, and salt until evenly distributed.
03 -
In a large bowl, whisk together brown sugar, eggs, yogurt, milk, vegetable oil, and vanilla extract until smooth and fully combined.
04 -
Pour the dry mixture into the wet ingredients and mix gently until just incorporated. Avoid overmixing.
05 -
Add chocolate chips or chunks to the batter and fold in until evenly distributed.
06 -
Divide the batter evenly between muffin cups, filling each to the top for a domed finish.
07 -
Bake in the preheated oven for 15 to 20 minutes, or until a skewer inserted into the center emerges clean of batter or crumbs.
08 -
Cool the muffins in the pan for 10 minutes, then transfer to a wire rack to cool completely or until slightly warm.