You can make the crescent tarts up to 6 hours ahead and fill them up to 4 hours before serving. Store covered in the refrigerator.
For creamy lemon tarts, try substituting lemon instant pudding and pie filling mix for the chocolate. Just omit the chocolate chips, and garnish with a little grated lemon peel.
Preheat the oven to 375 degrees F. Unroll the dough on a work surface, and press into a 12-by-9-inch rectangle. If using the crescent rolls, firmly press the perforations to seal. Cut into 6 rows by 4 rows to make 24 squares.
Gently press the squares into 24 ungreased mini muffin cups (the dough will not completely cover the inside of the cup; do not press too much). Bake until the edges are golden brown, 6 to 8 minutes. Cool completely in the pans, about 10 minutes. Remove from the pans.
Meanwhile, in a medium bowl, beat the milk and pudding mix with a wire whisk until the mixture begins to thicken. Fold in the whipped topping. Fill each cooled cup with about 1 tablespoon of the pudding mixture.
Spoon the whipped topping into sandwich-size re-sealable plastic bag; seal the bag. Cut the tip from 1 bottom corner of bag; squeeze the topping onto tarts, and sprinkle each with chocolate chips. Store in the refrigerator.