Begin heating your favorite spaghetti sauce over low heat, stirring occasionally.
In a separate skillet or small pot, brown the chopped onion in 1 tablespoon butter until caramelized. Add a pinch of oregano and/or Italian seasoning to the onions while they are cooking.
Once onions are caramelized, add them, along with the chopped green pepper, to the slowly heating spaghetti sauce. Add FRESH ground pepper to taste.
Into the same skillet or pot just used for the onions, put 1 tablespoon extra virgin olive oil, reserved juice from black olives, and 1 teaspoon tomato paste. Turn heat to LOW and reduce this until thickened (about 7-12 minutes). Watch carefully to avoid scorching/burning.
While this is reducing, add 2 tablespoons FRESH minced garlic, 1 tablespoon liquid smoke, 1/2 cup salsa (if using), remaining tomato paste, FRESH chopped tomatoes, 1 tablespoon butter, and meat and veggies (if using) to heating spaghetti sauce.
Cook spaghetti sauce until thick (no puddling). Turn off heat, remove pot from burner and let sauce sit about 5 minutes.
After 5 minutes, add 3 tablespoons sour cream, one at a time, stirring gently and thoroughly after each addition.
Incorporate the reduced olive oil, olive juice, and tomato paste mixture into spaghetti sauce.
Stir in enough Parmesan cheese to your liking.
Serve with hot noodles, cheesy garlic bread, and extra fresh grated cheese.