Heat the olive oil in a large Dutch oven over medium heat. Add the ground beef, turkey Italian sausage, removed from casings, and the onion. Cook, stirring often to crumble the beef and sausage, for 4-5 minutes. Add the carrots, roasted bell pepper, garlic, dried basil, dried oregano, crushed red pepper flakes, and sea salt and freshly cracked pepper, to taste. Add the beef stock, tomato paste, crushed tomatoes, and the tomato sauce to the beef mixture as well as the sugar. Stir until well combined. Cover with a lid and place into the oven for 3-4 hours.