Easy Chocolate Muffins

Preheat: Preheat the oven to 400 degrees Fahrenheit. Spray a standard 12-cup muffin tin with cooking spray or add muffin cup papers.

Make the batter: In a large bowl, whisk the all-purpose flour, cocoa powder, Dutch process cocoa powder, baking soda, espresso powder, and salt.

In a separate medium bowl, whisk milk and vinegar until frothy. Whisk in the brown sugar, granulated sugar, oil, and vanilla extract. Stir the wet ingredients into the dry ingredients with a spatula until a thick dough forms. Fold the chocolate chips into the batter.

Scoop the batter evenly into the muffin cups: the cups will be full to the top, using about a heaping ¼ cup per muffin. Sprinkle another handful chocolate chips onto the tops of the muffins.

Bake: Bake the muffins for 20 to 23 minutes, until puffed and a toothpick comes out clean. Cool for 5 minutes in the pan, then transfer to a rack to cool fully, about 1 hour. Eat immediately or they taste even better the next day after storage in a sealed container at room temperature. Store 1 to 2 days in a sealed container at room temperature, then transfer to refrigerator and refrigerate up to 5 days (allow to come to room temperature before serving). You can also freeze the muffins for up to 3 months.