Preheat the oven to 450F
Brown the sausage in a large skillet over medium-high heat until no longer pink
Meanwhile, cut the onion into thin slices
Remove the sausage from the pan and place on a towel-lined plate
Without cleaning the pan, add two tablespoons of oil, the sliced onions, and 1/2 teaspoon of salt
Cook the onions for about 10 minutes, stirring frequently, until brown and softened then remove from the heat
In a food processor, combine the kale, basil, parmesan, garlic, 2 tablespoons of oil, and 1/2 teaspoon of salt until smooth
Heat an oven-safe 12-inch skillet over medium heat for 2 minutes
Add 1 tablespoon of oil and cornmeal and swirl to coat the pan
Stretch the pizza dough over the pan to cover the bottom and sides of the pan
Cook the dough over medium-high heat for 2-3 minutes until the dough starts to bubble
Quickly spread the pesto on the dough, then top with the cooked sausage, onions, mozzarella cheese, and crushed red pepper
Brush any exposed crust edges with oil
Place the entire skillet in the oven and bake for about 12-15 minutes, until the crust is golden brown and the cheese has melted