Preheat your oven to 400°F.: As the oven warms, notice the dry, warm scent that signals the air inside is ready to crisp pizza edges. Preheating ensures the naan goes into a hot environment so the bottom becomes golden while the cheese melts on top. Place an oven rack in the middle position for even heat distribution. A common mistake is placing the rack too low which leads to an overly browned bottom, so set it centered and give the oven at least 10 to 15 minutes to stabilize.
If using diced or whole tomatoes, use an immersion blender or food processor to process your tomatoes until they are the consistency of salsa.: The moment you blend, you will hear a faint whirl and smell intensified tomato brightness, which is a cue that the sauce base is ready. Achieving a chunky but saucy texture helps the mixture cling to the naan without sliding off. Pulse in short bursts to control texture and avoid turning the tomatoes into watery purée. Over processing can remove texture and lead to a thin sauce; stop when there is still some body.
In a large pot, over medium heat, heat oil. Add garlic and cook until lightly golden, 30 seconds to a minute. Carefully add tomatoes—oil will sizzle and pop as you do. Stir in sugar and basil. Bring mixture to a simmer.: When the extra virgin olive oil shimmers gently, add the garlic and inhale that warming aroma as it turns lightly golden. That brief toasting releases aromatic sulfur compounds that deepen the sauce. Pouring in the tomato will cause lively sizzling from the hot oil, which is okay it helps to bloom flavors but keep a distance to avoid splashes. Stir in the sugar and basil to marry acidity and herb notes, and watch as small bubbles form signaling a simmer. If garlic browns too quickly, remove the pot from heat briefly to stop it from turning bitter.
Turn heat down as needed to keep at a good simmer and cover with a splatter screen if you have one. Simmer for 20 to 30 minutes, stirring occasionally, until sauce has thickened and reduced to about 1 1/2 cups. If you don’t own a splatter screen and the sauce is popping too aggressively, turn it down and extend the simmer time as necessary.: The sauce will move from juicy to jam like, and that visual thickening is your best guide. Stir occasionally to prevent sticking and to check flavor concentration. A well reduced sauce smells sweeter and more tomato forward, and it will coat a spoon rather than pour freely. Rushing this step leaves watery sauce that can sog the naan , so accept a longer simmer if needed and be patient.
Add salt to taste.: After reduction, flavors concentrate so salt needs careful adjustment. Sprinkle small amounts, taste, and wait a moment for the sauce to open up before adding more. Proper seasoning brightens all layers, and a sauce that tastes flat will make the final pizza dull. Avoid adding too much at once since you cannot remove salt once mixed in; if you overdo it, counter with a small splash of acid if available, or add unsalted ingredients to balance.
Place naan loaves on baking sheets. Cover each with about 1/3 heaping cup of sauce. Top with 1/2 cup of cheese each and desired toppings.: The tactile step of assembly is satisfying, feel the warm air from the oven as you work. Spread the sauce leaving a narrow edge so the crust crisps properly, and distribute the mozzarella in an even layer so it melts uniformly. Add toppings like sliced pepperoni , tomato , and bell pepper with balance in mind to avoid overcrowding. A common error is piling on too many wet toppings which can produce steam and sogginess, so space things out for better texture.
Bake for 12 to 14 minutes, until cheese is melted and naan is golden. If baking all 4 pizzas at once, swap top and bottom trays once halfway through and keep an eye on the bottom tray to make sure the crust is not burning.: In the oven you will hear a gentle bubbling as the cheese melts and see edges turn golden brown; that sizzling is your cue to check for doneness. Rotating trays ensures even heat exposure, and watching the bottom prevents over browning. If the cheese is melted but the crust needs more color, move the pizza briefly to a higher rack for a minute or two. Avoid opening the oven repeatedly because each peek reduces overall temperature and can extend bake time.
Cool on the baking sheet for 5 minutes before slicing, and enjoy!: Letting the pizzas rest lets the melted mozzarella set slightly so slices hold together better, and the crust firms as steam dissipates. During this pause, aromas will concentrate and the texture improves. A typical mistake is cutting immediately which can cause toppings to slide; patience yields cleaner slices and a more pleasant eating experience.