1Heat oven to 450ºF. Grease cookie sheet. Stir Bisquick, 1/3 cup mayonnaise and the milk in medium bowl until soft dough forms. Press dough into 12x8-inch rectangle on cookie sheet.
2Bake 8 to 10 minutes or until golden brown.
3Mix turkey, onions, bacon and 1/4 cup mayonnaise. Spoon over crust to within 1/4 inch of edges. Sprinkle with tomato and cheese. Bake 5 to 6 minutes or until mixture is hot and cheese is melted.