Heat olive oil in a large skillet or Dutch oven over medium heat. When the oil shimmers, add the beef and cook, stirring, until the meat is no longer pink, about 7-9 minutes. Drain off the fat, leaving the beef in the pan.
Stir in the salt, Italian seasoning, garlic powder, onion powder, sugar, broth, pasta shells, and tomato sauce. Bring to a boil, then reduce the heat to low or medium-low so the liquid is at a gentle simmer. Cover and cook until the pasta is tender, about 8-10 minutes, stirring occasionally so that the pasta cooks evenly and doesn’t stick to the bottom of the pan. Remove from the heat.
Stir in heavy cream, Velveeta, and cheddar. Stir until the cheese melts. Taste and season with additional salt and pepper, if necessary.
Garnish with Parmesan, herbs, or green onions; serve immediately.