Dissolve yeast in warm water. Add 1 1/2 cups flour and mix with large spoon.
Add oil, rosemary and salt, mixing well.
Mix in the rest of the flour and turn out onto a well-floured surface; knead for 5 minutes. Add more flour until dough is no longer sticky.
Rinse and dry the bowl and lubricate with olive oil. Return dough to bowl, turning once to cover in oil.
Cover dough with clean kitchen towel and let rise for 1 hour in a warm place in the kitchen.
Preheat oven to 425 degrees F and divide dough into two or three pieces, depending upon pan size and crust preference; on flat, floured surface roll out each piece to approximate pan size.
Sprinkle each pan with a light dusting of cornmeal and lay dough in the pans. Oil your fingertips and press pizza dough into each pan.
Lightly precook the crust before adding sauce and toppings. You want the dough to rise enough in the oven to form bubbles but remove before it begins to brown, less than 5 minutes.
Add your own toppings and bake for 15-20 minutes depending on your own toppings.