Heat the olive oil and butter in a pan. Add the bacon and cook until lightly crisp. Add the onion and garlic; cook just until fragrant.
Add the rest of the vegetables, mushrooms and black olives to the pan. Sprinkle with salt and pepper. Cook over medium-high heat just until the vegetables are done. DO NOT OVERCOOK.
Throw in the cooked pasta and toss to coat each noodle with oil.
Turn off the heat. Add the parsley and toss to blend. Taste, add more salt and pepper, if needed. Serve hot.