Preheat oven to 400 degrees. Unroll pizza dough on lightly floured surface. Pat out dough to form 16 x 12-inch rectangle. Cut into quarters.
Top dough with ham to within 1/2 inch of sides. Mix cheese and dressing; spread on ham. Top with tomatoes. Fold each rectangle in half; seal edges with fork. Put on baking sheet sprayed with cooking spray.
Bake 16 to 18 minutes or until golden brown.
Make ahead: prepare calzones up to 8 hours in advance. Wrap baking sheet with plastic wrap and store in refrigerator. When ready to eat, unwrap and bake one or more as directed.
Healthy Living Tip: Save 50 calores and 7 grams of fat per serving by preparing with Kraft 2% Milk Shredded Reduced Fat Colby & Monterey Jack Cheese and Kraft Light Ranch Reduced Fat Dressing.