Step 1

Heat the oil in a large nonstick skillet over medium-high. Add the onions and celery, and cook, stirring often, until the vegetables are just tender, about 6 minutes. Transfer the vegetable mixture to a 5- to 6-quart slow cooker.

Step 2

Add the chopped tomatoes, mushrooms, tomato paste, strained tomatoes, wine, zucchini, garlic, oregano, and salt to the slow cooker; stir well. Cover and cook on LOW until the mixture has thickened, about 5 hours and 30 minutes. Divide the cooked linguine evenly among 6 plates; top evenly with the marinara sauce, cheese, and basil.