Preheat the oven to 475 degrees F.
Roll and stretch out the risen dough on a floured work surface into a rope about 31 inches long. Press a rolling pin into the dough to create a trench and roll it to a rectangle about 3 inches wide.
Keeping a 1/2-inch border on each long side of the dough, smear the remaining dough with the olive oil and sprinkle with salt. Spread the surface with a nice thin layer of the Arrabbiata Sauce, then sprinkle with the Parmesan, mozzarella and pepperoni. Arrange the string cheese pieces on top in a double line. Fold the long sides of the dough up over the center (over the string cheese) and pinch the edges together well so there's no leakage. Bring the ends together to form a circle.
Drizzle a baking sheet with olive oil. Carefully transfer the dough circle to the prepared baking sheet, flipping it over before putting it on the sheet so the seam side is down. Brush the egg wash over the surface of the dough. Bake until the edges of the crust are golden brown and the cheese is melted and bubbly, about 15 minutes. Transfer to a board to rest for 10 minutes before cutting.
Arrange the tomato slices and basil leaves in concentric circles in the middle of the pizza crust ring and serve with a dish of the remaining Arrabbiata Sauce on the side for dipping.
Heat a pan over medium-high heat until hot and add the olive oil. Throw in the red pepper flakes and onions, give them a stir and cook until softened, 2 to 3 minutes. Add the garlic and cook for 30 seconds. Add the wine, whisking to deglaze the bottom of the pan. Cook until the liquid reduces by half. Add the crushed tomatoes and Italian seasoning and stir to combine. Add a pinch of sugar and some salt. Bring to a simmer, reduce the heat to low and simmer for 30 minutes.