Take the dough out of the fridge 2 hours prior to using. Do not uncover the bowl. Oil the bottom of a 12 by 16 Grandma pizza sheet pan (or standard half sheet pan) with 3/8's cup of olive oil. You need to use a lot of oil!
Drain the crushed plum tomatoes and season with a 1/2 teaspoon of kosher salt. Save the juice for another use.
Remove the dough from the bowl and place it into the pan. With your fingertips begin pressing the dough into the corners of the pan. You will not be able to do this in one attempt. Place plastic over the pan and let the dough warm up.
After 45 minutes remove the plastic and try to stretch it again to the size of the pan. Cover with plastic wrap and repeat process one more time until the dough has completely filled the pan. Cover the dough and set aside. Preheat oven to 450f and set one rack to the lowest level of the oven and one to the highest.
Mince the garlic and add to a bowl with 3 tablespoons of olive oil to create the garlic oil. Mix 2 teaspoons of Calabrian chili paste with 2 tablespoons of olive oil to make the chili oil.
Remove the plastic from the pan and if required press the dough into the edges. Starting with a corner, layer the mozzarella cheese in an overlapping shingle pattern, leaving the outside 1/4 to 1/2 inch uncovered. Make sure the dough is layered completely with the mozzarella slices.
Next, add the drained plum tomatoes to the pizza. You can use 45-degree lines or spoon the sauce all over. Leave some open areas. Don’t coat it all. Add the pepperoni to the pizza. It may look crowded but the pepperoni will shrink when baking. Take the garlic oil and drizzle 3 tablespoons of the oil and garlic pieces all over the pizza.
Place the pizza onto the lowest rack and cook for 12 minutes rotating the pan 180 degrees after 6 minutes.
After 12 minutes remove the pizza from oven and check the bottom for browning. If the pizza is well-browned, bake on the top rack for 6 more minutes. Otherwise, leave the pizza on the bottom rack for 6 more minutes.
After 18 minutes of baking remove the pizza. Drizzle the Calabrian chili oil according to taste (it's spicy!), and sprinkle the oregano and Pecorino Romano all over the pizza. Bake for 2 minutes more on the top oven rack.
If the pepperoni pizza is not crisp enough on top you can broil it for 30-60 seconds. Watch very carefully though!
The total cooking time will be approximately 20-22 minutes. Remove the pizza from the pan and let cool for a couple of minutes on a wire rack before slicing. Enjoy!