Proof the yeast:
In a small bowl, mix warm water with sugar and yeast. Let sit for about 5 minutes until it starts to bubble.
Mix the dough:
In your stand mixer, combine the flour and salt. Add the bubbly yeast-water mixture and mix until combined. Knead a few times by hand until soft.
Let it rest:
Place the dough in a bowl, cover with plastic wrap, and let sit overnight at room temperature. It won’t rise much, just a little puffier.
Form pizza balls:
Pinch off smaller balls of dough and place on a cookie sheet. Cover with plastic wrap and let rise another hour.
Preheat the grill to 450°F.
Roll each ball into a 5–6" or make two large pizzas. Brush one side with olive oil and place on the grill, oiled side down, for 4 minutes. Remove from grill, add toppings to the grilled side, and return to the grill for another 4 minutes until the cheese is melted and bubbly.