Heat oven to 400°F. Grease large cookie sheet. Unroll dough on cookie sheet. Press to 14x8-inch rectangle. Fold both long sides over about 1/2 inch to form rim, pressing to seal. Bake 8 minutes.
Spread dough with pesto. Arrange asparagus and onion on dough. Sprinkle with cheeses.
Bake 8 to 10 minutes or until edges are golden brown and cheese is melted. Cut crosswise into 14 (1-inch) strips. Cut in half lengthwise to make 28 pieces. Serve warm or cool.