To Make the Dough:

1. In a countertop mixer fitted with the dough hook attachment, combine the dry ingredients (flour, salt, and yeast) and mix well. Add the water and mix on low speed for 3 minutes, or until the dough begins to come together.
2. Add 1/4 cup of olive oil and mix on low for another 1 minute. Increase the speed to medium and mix for 3-4 minutes. (Tip: If the dough doesn’t want to form a ball after adding the olive oil, just add 1-2 tablespoon of additional flour to the bowl.)
3. Transfer dough to a large, oiled bowl. Cover and place in a warm (85°F) location for 75 minutes.
4. Flip dough out onto a well floured countertop and gently fold it several times. Transfer dough back into the oiled bowl, cover, and place in a warm location for another 75 minutes.
5. Brush the bottom and sides of a 12" cast iron skillet with 1 tablespoon of olive oil. Gently stretch or roll dough into a large circle and then press into the bottom and up the sides of skillet.

To Make the Pizza:

1. Preheat oven to 450°F.
2. Layer sliced mozzarella evenly across the top of the dough.
3. Spread the sliced pepperoni and onions evenly on top of mozzarella.
4. Spread the pizza sauce evenly on top. Scatter chopped tomatoes on top of the sauce.
5. Top pizza with grated Parmesan, and brush top edge of the dough with remaining 1 tablespoon of olive oil.
6. Bake at 450°F for 20-22 minutes, or until crust is golden brown. Allow pizza to cool for 5 minutes before slicing.