These are something my kids really love because they get to make their own. I've seen them done with Portabello mushrooms instead of the English muffin too for a low-carb option, but I've never tried that.
This is my basic sauce for any pizza:
1 can tomato sauce
1 can tomato paste
1-2 T. Italian seasoning
(I ALWAYS buy the Hunts paste and sauce that is pre-seasoned like "garlic" or "oregano")
Cut English Muffins in half and place on a cookie sheet- cut side up.
Cover each with sauce, then top with cheese and your favorite toppings.
Bake at 400 for 10 minutes or until cheese is golden.