Pizza grilled on a pizza stone tastes as awesome as it looks, but you pretty much get the same pie as you would baked in a hot oven. Pizza grilled directly on the grill grate delivers a totally different experience in technique, texture, and taste.
When you do it right, the dough bubbles and blisters, producing a smoky, crackling crust on both sides. Direct grilled pizza demands a different set of tactics. Unlike conventional pizza, you stretch the dough in oil on a sheet pan rather than in flour. You grill the dough first to cook one side through, then add the toppings. These go in the reverse order of how you’d arrange them on a conventional pizza: cheese first (so it melts on the hot crust), then cooked toppings, and last of all, the sauce.
The grill setup differs, too: You heat one zone to medium-high to sear the dough, leaving the other zone low to keep the crust warm while you lay on the toppings. Okay, all this sounds a lot more complicated than it really is. In keeping with the unusualness of the grilling method, I give you an equally unusual topping of potatoes, broccolini, and Italian sausage.
Step 1: Bring the water and 1 tablespoon of salt to a boil. Add the potatoes and boil until almost tender, 2 minutes. Transfer with a wire skimmer or slotted spoon to a colander to drain, rinse with cold water, then drain again. Set the potatoes aside in a bowl.
Step 2: Add the broccolini to the boiling water and blanch for 2 minutes. Drain in a colander, rinse with cold water, then drain again.
Step 3: Brown the sausage and onion in a large heavy skillet over medium heat, chopping the sausage with the blade of a spatula to break it up. This will take 5 to 8 minutes. Increase the heat to high the last 2 minutes and stir in the potatoes and broccolini. You want to brown the potatoes. Drain off the excess sausage fat and let the mixture cool to room temperature. The toppings can be prepared up to a day ahead of time if covered and refrigerated.
Step 4: Set up your grill for direct grilling. One burner should be set on medium-high, the other on low. It doesn’t hurt to have a fire-free safety zone in case the pizza starts to burn.
Step 5: Generously oil a rimless sheet pan and place one of the dough balls in the center. Pat the dough flat, then stretch it out into an oval or a rectangle about 9 by 12 inches and ¼ inch thick. Generously oil the top.
Step 6: Carry the sheet pan with the crust to the edge of the grill. Brush or scrape the grill grate clean and oil it well. Gently and carefully lift the dough by one end and drape it flat on the grate over the hot section of the grill. Grill until the top bubbles and blisters and the bottom browns, 3 to 5 minutes.
Step 7: Slide a wide-bladed spatula under the crust, and with the aid of tongs, move it to the cooler section of the grill. Brush it with olive oil and turn it over. Spread half the grated cheese on top of the crust (on the grilled part). Arrange half the sausage mixture, potatoes, and broccolini on top. Sprinkle with half the Parmigiano-Reggiano and half the hot red pepper flakes. Drizzle with more olive oil.
Step 8: Slide the pizza back over the hot section of the grill. Close the grill lid to concentrate the heat. Continue grilling until the cheese has melted, the toppings are sizzling, and the crust is browned on the bottom, 3 to 4 minutes. Transfer to a cutting board and cut into squares for serving. Prepare the remaining pizza the same way.