THE TOPPING: Heat the oil in a large skillet over medium-high heat. Add the onions and sprinkle with salt. Cook, stirring constantly, until the onions start to wilt, about 5 minutes. Lower the heat to medium-low and continue cooking, stirring often, until the onions are very soft and browned (this will take at least 30 minutes). Remove from the heat.

TO ASSEMBLE: Preheat the oven to 450°F. Lightly oil a sheet pan and sprinkle lightly with semolina. Oil your hands. Press the dough out on the pan with your fingertips, shaping it into a smooth, thin round. Strew the caramelized onions evenly over the top, leaving a 1 inch edge. Season with black pepper.

Bake for 10 minutes. Crumble the Gorgonzola over the top of the pizza and sprinkle with the chives. Bake for 5 to 10 minutes longer, until the crust is crisp and browned and the cheese is melted.