In large bowl, dissolve yeast in 1/4 cup lukewarm water. Add 1/4 cup flour and the sugar, stir together. Cover with plastic wrap and let rise in a warm place for 20 minutes.
Stir the remaining 1 cup lukewarm water, 3 cups flour, the cornmeal and salt into the yeast mixture.
Combine the butter and garlic; mix into the dough.
Turn out onto a lightly floured work surface and knead until soft and elastic, 10-12 minutes (I let my kitchen aid do this).
Lightly grease a large bowl, add the dough and turn to coat. Cover and set in a warm place until the dough is doubled in size, 1 hour.
Punch dough down, then knead for 2-3 minutes (again I let the kitchen aid do this part).
Grease a 9x13-inch baking pan (I used glass), then press in dough to cover the bottom and 2 inches up the sides; let rise for 20 minutes.
Preheat the oven to 500 degrees. Top the pizza dough with your favorite toppings. Lower the oven to 450 degrees and bake for 30 minutes.