In a large bowl proof the yeast with the sugar in 1/3 cup lukewarm water for 10 minutes or until it is foamy. Stir in an additional 1/3 cup lukewarm water, the oil, 2 cups of the flour, and the salt and blend the mixture until it forms a dough. Knead the dough on a floured surface, incorporating as much of the remaining 1/4 cup flour as necessary to prevent the dough from sticking, for 5 to 10 minutes, or until it is smooth and elastic.
Alternatively, the dough may be made in a food processor. Proof the yeast as described above and in a food processor combine it with the remaining ingredients. Process the mixture until it forms a ball, adding more water, 1 teaspoon at a time, if it is too dry, or more flour, 1 tablespoon at a time, if it is too wet, and knead the dough by processing it for 15 seconds.
Put the dough, prepared by either method, in an oiled bowl and turn it to coat it with the oil.
Let the dough rise, covered with plastic wrap, in a warm place for 1 hour, or until it is double in bulk, and punch it down.
Sprinkle an oiled 14-inch black steel pizza pan or black steel baking sheet with the cornmeal. roll out the dough on a lightly floured surface into a 14-inch round and fit it into the pan Bake for 5 minutes. Brush with melted butter and sprinkle with chocolate chips and sugar.
Bake the pizza on the bottom shelf of a preheated 500 degree electric oven or on the floor of a preheated 500 degree gas oven for another 5 to 10 minutes.