Ranch Chicken Pizza

1/3 pound bacon, chopped
2 skinless, boneless chicken breasts, cut into bite-sized pieces
1 (1 lb.) store-bought or homemade pizza dough
1/2 cup Ranch salad dressing
1 cup shredded mozzarella cheese
1 cup shredded cheddar cheese
1 cup chopped tomatoes
1/4 cup chopped green onions

Preheat the oven to 425F.  Preheat pizza stone, if using.  If not, grease a pizza pan or medium baking sheet.Place the bacon in a large skillet over medium-high heat.  Cook until crispy.  Remove with a slotted spoon.  Add the chicken pieces and cook until no longer pink in the center.Roll out the dough to a circle.  Bake the crust for 5-7 minutes in the preheated oven, or until it just begins to turn golden brown.  Remove from oven.Spread the ranch dressing over the partially baked crust.  Sprinkle on the mozzarella cheese.  Add the chicken, bacon, tomatoes and onions, then top with the cheddar cheese.  Return the pizza to the oven and bake until the cheese is melted and bubbly, 10-15 minutes.