Preheat the oven to 400 degrees F (200 degrees C). In a medium bowl, mix together the flour, cornmeal, sugar and baking powder. Stir in the milk, oil and eggs, mixing until just moist. Spread in a greased 12 inch deep-dish pizza pan, or a 10x15 inch baking pan.
Bake the crust for 10 minutes. Remove from the oven, and sprinkle with 1 cup of the cheese. Bake for another 10 minutes.
Spread the refried beans and mayonnaise over the melted cheese. Top with blue cheese dressing, turkey chili, and remaining cheese.
Bake for 12 to 15 more minutes in the preheated oven. Top with lettuce and diced tomatoes before slicing and serving.