Whats the best way to reheat leftover pizza? We usually use Boboli Crust with our own toppings, or sometimes we have frozen pizza.
@Cos is right, a pizza stone is great - so is a pizza screen in the oven.
If I don't want to heat up the oven (big oven, little piece of pizza aways seems like a waste), then a cast iron pan over medium heat on the stove with a lid does pretty well.
I have always had the most satisfactory results from preheating the oven to 400F with a pizza stone and then setting the cold pizza on the hot stone for 8 to 10 minutes?
If you just want to reheat a slice or two, you can warm it in the microwave for 30 seconds to a minute and then put it in a toaster oven on toast or a hot oven setting for a few minutes. It's best in the toaster oven if you put the slice(s) on the broiling rack on top of the baking sheet.
Since I prefer thin crust pizzas, oven re-heating often results in something resembling a burnt cracker with some half-cold toppings on it.
To avoid this, I "fry" leftover pizza to reheat it: I place a tiny bit of oil or butter into the bottom of a non-stick skillet, add slices of pizza, cover, and place over very low heat until the cheese is re-melted.
This method allows the pizza to warm and steam gently, while also ever-so-slightly frying the bottom of the crust, so one ends up with something very near the consistency of a fresh slice rather than a dried-out, inconsistently-warmed leftover.
This technique works with everything from thin crust to deep-dish pizza; only the reheating times are different.
I like to put a heavy sheet pan in the oven and preheat it to 350°F. Then I just slide my leftover slices onto the hot pan and bake for 5 minutes. The hot pan crisps up the bottom of the crust and the hot oven does the rest. Does a nice job of bringing a good slice of pizza back to life.
I found that a short burst in the microwave heats up up the whole piece. Then, you have to immediately put it into a very hot oven to get it crispy on the outside. (You said "the best way", not the most energy efficient.)
I use an oven at 250°F for a longer period of time--usually about 15 minutes, with the pizza either in or on tin foil. This seems to work well, it heats the pizza but doesn't toast the crust.
Pizza stone on 350 for 10 minutes. Or if your lazy and don't own a pizza stone, like me, toaster oven on toast for however long it takes too heat, crisp up and not burn.
With a waffle iron!!! Leftover Pizza + Waffle Iron = Delicious Crispy, Gooey, Cheese-Stuffed Snack
For larger amounts of leftover frozen thin crust pizza- Line a medium/large baking pan/sheet that has at least 1/4 inch vertical sides on it with tin foil. Use middle rack. If two baking pans are used, use rack positions 1 and 4. 1 being the lowest rack, 4 being the higher one. Preheat oven on Convection/Bake at 425F to 450F. After preheating oven, place frozen thin crust pizza on baking pan/s. Put pan/s in oven and heat for approx 30 minutes. Check at 20 minutes to make sure not to over cook. Enjoy!