Preheat oven to 375°F.
Place large skillet over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the meat to the pan and cook until golden brown, 5-6 minutes.
Add the onion and chili powder to the pan, season with salt and pepper, and cook until the onion is tender, 4-5 minutes.
Add the mustard, ketchup, Worcestershire sauce and beef stock to the pot, bring up to a bubble and simmer until thickened, 4-5 minutes. Let cool.
Dust your hands and lightly coat the pizza dough with flour or cornmeal before rolling it out onto a work surface. Roll out the dough slightly so it's approximately 11x16".