Preheat the oven: Heat to 475°F (245°C). If you have a pizza stone or steel, place it in the oven while it heats.
A hot surface is key for a crisp bottom.
Prep the dough: Let your dough rest at room temperature for 30–45 minutes so it stretches easily. Lightly dust your counter with flour and shape the dough into a 12–14 inch round.
Prep the toppings: Shred the chicken. Slice the sun-dried tomatoes.
If using dry-packed tomatoes, soak them in hot water for 5–10 minutes to soften, then pat dry.
Stretch and transfer: Stretch the dough from the center outward, leaving a slight rim. Move it to a cornmeal-dusted peel or an oiled baking sheet.
Sauce it: Spread 1/2 to 3/4 cup pesto over the dough in a thin, even layer. Don’t over-sauce; pesto is rich and can make the crust soggy if too thick.
Add the cheese and toppings: Sprinkle on half the mozzarella, then add chicken and sun-dried tomatoes. Scatter a few thin onion slices if using.
Top with remaining mozzarella and the Parmesan. Lightly season with black pepper.
Bake: Slide the pizza onto the hot stone/steel or place the sheet on the middle rack. Bake 10–13 minutes, until the crust is golden and the cheese is bubbling with a few browned spots.
Finish: Brush or drizzle the crust edge with a little olive oil for sheen and flavor.
Add fresh basil and a pinch of red pepper flakes if you like heat.
Rest and slice: Let the pizza rest 2–3 minutes so the cheese sets. Slice and serve hot.