Preheat oven to 350 degrees F (175 degrees C). Line 12 muffin cups with paper liners.
Mix flour, baking powder, and salt together in a bowl.
Beat sugar, butter, and lemon zest together in a large bowl until smooth. Add eggs and banana to the sugar mixture; beat until smooth. Stir about 1/3 of the flour mixture into the sugar mixture to integrate fully into a batter; repeat with remaining flour mixture in two even additions. Fold beets and chocolate chips into the batter; spoon into the lined muffin cups.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 30 to 40 minutes. Cool in the pans for 10 minutes before removing to cool completely on a wire rack.
Chocolate Beet Muffins · Dinner Match Lab | Dinner Match Lab