Frozen Breakfast Pizza?

I would like to bring homemade pre-cooked, frozen breakfast pizzas to my friend who's about to have a baby. I have a great recipe for pizza crust and have toppings (scrambled eggs, bacon, cheese, and country gravy), I just need to know the best way to reheat the pizzas if they're fully cooked and completely frozen so I can tell my friend and her husband how best to reheat them. If the crust is fully baked and the toppings on the crust have been fully cooked in the oven, should they reheat the pizza in the oven or the microwave? If in the oven, on a cookie sheet or on only the rack? and should they thaw the frozen pizzas first? If it makes a difference in reheating time, I'm planning on making small individual pizzas with a medium thickness crust, what hand tossed would be. Any help or suggestions would be great! Thank youFrozen Breakfast Pizza?
I would set the oven to 450. and heat for 15 min. make sure to check and make sure the cheese is melted and the crust is crisp on the bottom. :)