For the dough, combine the water, yeast, sugar and olive oil and let stand for 5 minutes until foamy. In a large bowl, mix together the flour and salt. Add the wet ingredients to the dry and stir until it forms a shaggy dough.  Turn the dough onto a lightly floured work surface and knead for 10 minutes until the dough is smooth and elastic. (Alternatively, the dough can be mixed in the bowl of a stand mixer using a dough hook.)

Gather the dough into a ball, transfer to an oiled bowl and cover. Place the bowl in a warm spot to allow the dough to rise until it has doubled in size, about 2 hours.

For the tomato sauce, heat the olive oil in a large skillet until it is shimmering. Sauté the garlic cloves for a few minutes letting them get fragrant. Add the tomatoes, salt, pepper and red pepper flakes and simmer for 20-25 minutes until the sauce has slightly thickened.  As the sauce is cooking, break up the tomatoes using the back of a wooden spoon or a potato masher. If you prefer a smoother consistency, when the sauce has finished cooking, transfer it to a blender and puree.

When the dough is ready, give it a quick knead and divide it into 4 equal portions. On a lightly floured work surface roll out the dough into a rough circle or oval. (They do not need to be perfectly round.)

Preheat a gas or charcoal grill on high heat. Place the rolled dough directly on the grates and grill for 2-3 minutes with the lid closed until the crust has grill marks and has puffed up. Flip and grill for an additional 2 minutes.

Remove the crusts from the grill and turn them over so the first side that was grilled is facing down.  Spread the sauce leaving a 1/2-inch border at the edge and sprinkle on the cheese and other toppings.

Return the pizzas to the grill and cook until the cheese has melted, about 1-2 minute. You may need to lower the heat  or move the pizzas to a cooler part of the grill to make sure the crusts do not burn.

Top with Parmesan and basil before serving.

Note: If you have extra tomato sauce, store it in the refrigerator up to 5 days or keep it in the freezer up to a month. The tomato sauce also works well on pasta.