This isn't really a recipe, more of an ingredient list. First, make your favorite pizza crust. My favorite recipe is out of The Tightwad Gazette, and I'm happy to share it if anyone wants it. It's a yeast crust that requires no rising. And it's good!
Anyway, to make BBQ chicken pizza, I usually use the following ingredients. You can substitute whatever you want based on what your family will eat!
BBQ sauce (whatever is your favorite. We like Bulls Eye)
Cooked, chopped chicken*
Chopped bell peppers
Chopped green onions
shredded cheese - I use a blend of mozzarella, cheddar, and pepperjack
Use the BBQ sauce in place of the tomato sauce you'd normally put on pizza. Top with the remaining ingredients. Some people put the cheese on the bottom, some put the cheese on the top. I do a little of both. Bake according to your pizza crust instructions.
*note: I always keep a supply of cooked, chopped chicken on hand in the freezer. I buy legs and thighs when they go on sale for 59 cents a pound. Then I boil them up, let them cool, take the meat off the bones, return the bones to the pot, and simmer it some more (voila! Chicken broth!). I chop the meat and freeze it in two cup portions. Two cups is about right for the two of us for casseroles. I use a little less on pizza.