Combine the ground beef and Italian sausage in a bowl. Add 2 cloves of minced garlic, 1½ teaspoons chili powder, 2 Tablespoons granulated sugar, ½ teaspoon garlic powder, 1 teaspoon salt and ½ teaspoon pepper.
Using your clean hands or a wooden spoon, mix the spices into the meat until fully incorporated.
Brown the seasoned hamburger and sausage mixture over medium heat in a Dutch oven or heavy-bottomed pot.
Once meat is browned, drain any excess fat.
Add the diced tomatoes, tomato sauce, drained and rinsed kidney beans, peppers, onion and remaining spices and sugar. Stir well to combine.
Bring to a simmer, then reduce heat to medium-low. Simmer covered, stirring occasionally, for at least 30 minutes, but preferably longer to let the flavor develop.
Just before serving, add ½ teaspoon vinegar, and stir.
Garnish with green onions, sour cream, shredded cheese and jalapeño peppers, if preferred. Serve with tortilla chips.