Combine flour, yeast, salt, oil, and warm water in a large bowl. Using a wooden spoon, mix until no dry flour remains. Make sure the bowl is nice and large to accommodate for rising.
Cover bowl tightly with plastic wrap and let sit on a counter for 8-24 hours. Dough will rise quite a bit.
Once fully rested, sprinkle top of dough with flour and turn out onto a well floured surface.
Divide dough into 2 portions, shape each into a ball/disk... tucking dough under itself to form a tight ball.
If desired, place one of the balls in a ziploc bag for freezing.
Pour some oil (a couple tablespoons) in the bottom of the cast iron pan, place ball of dough in pan, turning to coat in the oil.
Using your hand, push the dough around to spread the oil in the pan.
Cover tightly with plastic wrap and let rest for 2 hours.
Preheat oven to 550 degrees (or as high as your oven goes)
Once dough has rested, it should have settled and puffed to fill the pan. Use your fingers to push the dough into all edges of the pan and remove large air bubbles.
Lift up edges of the dough to eliminate any air pockets on the bottom of the dough.
Top the dough with your pizza sauce, cheese and any desired toppings or seasonings. Drizzle with olive oil.
Place skillet in oven and bake for 12-15 minutes. The top should be bubbly and golden brown.
Use a spatula to lift the edge of the pizza and check to see if the bottom is nice and golden brown and crisp. If you'd like it crispier, place on a stovetop burner over medium heat for a couple of minutes.
Sprinkle pizza with grated parmesan cheese and/or fresh basil. Slice into pieces and serve hot.