While you’re waiting for the oil to heat up, heat a large skillet over medium heat. Add the olive oil. Add the onions and garlic, stirring well and cook until translucent, about 2 minutes. Add in the beef, breaking it up with a large wooden spoon. Cook until browned, about 6 to 8 minutes. In a small bowl, combine the chili powder, cumin, paprika, onion powder, cayenne, salt and pepper. Add it to the beef and stir well (continuing to break up the pieces of beef with the spoon) until combined, then stir in the stock. Toss well to combine. Cover and cook on low heat until the tortillas are finished. (note: if i ever find that the stock turns the mixture too watery, i will sprinkle in a spoonful or flour or cornstarch and stir stir stir, sometimes drizzling in a bit more stock.)