Preheat oven to 400 degrees F. In a small bowl, stir together flour, cocoa powder, and salt; set aside. In a medium bowl, slightly beat egg with a wire whisk. Whisk in milk, oil, and flour mixture until combined.

Lightly coat an unheated nonstick griddle and twenty 1-3/4-inch muffin cups with nonstick cooking spray; set muffin cups aside. Preheat griddle over medium heat. For each crepe, spoon 1 tablespoon of the batter onto griddle (hold spoon close to griddle when spooning and pour slowly to make circles). Cook for 30 to 60 seconds or until bottom is golden brown and top appears dry. (You can cook multiple crepes at a time.) Use a spatula to remove crepes to paper towels, browned sides up. Repeat with remaining batter. If desired, when cool enough to handle, trim edges of crepes. Gently press crepes, browned sides down, into prepared muffin cups, pleating as necessary to fit.

Bake crepe cups about 12 minutes or until edges are browned and crepes appear to hold their shapes. Cool in muffin cups on wire racks. Carefully remove from muffin cups.

In a medium bowl, fold together whipped dessert topping and yogurt. Cover and chill until ready to use or up to 24 hours.

Just before serving, spoon yogurt mixture into crepe cups. Top each cup with a berry. If desired, garnish with fresh mint leaves. Makes 20 crepe cups.

Make-Ahead Hint: Crepe cups can be baked and stored in a tightly covered container for up to 3 days. Yogurt mixture can be stored in the refrigerator overnight.