Easy Crockpot Spaghetti Sauce

8 ounces Italian sausage
1 pound lean ground beef
2 cans (14.5 ounces each) diced tomatoes with juice
1 cup chopped onion
1 can (8 ounces) tomato sauce
1 can (6 ounces) tomato paste
1/2 cup chopped green bell pepper
1 to 2 tablespoons sugar
1 to 2 teaspoons salt, or to taste
2 cloves garlic, crushed
2 teaspoons dried leaf basil
dash ground red pepper or red pepper flakes, if desired

Remove sausage from casings; brown in a heavy skillet along with ground beef. Break up sausage and ground beef while browning; drain well.

Add sausage and beef to crockpot, along with all remaining ingredients. Cover and cook on LOW setting for 8 to 10 hours or HIGH for 4 to 5 hours. Serves 8 to 10. This sauce can be frozen.