In a 5-quart kettle bring 4 quarts salted water to a boil for cauliflower (or cauliflower mixture) and pasta. In a 12-inch deep heavy skillet heat 1 1/2 tablespoons oil over moderate heat until hot but not smoking and cook bread crumbs, stirring, until golden. Transfer bread crumbs to a bowl and wipe skillet clean with paper towel. In skillet cook bacon over moderate heat until crisp.
While bacon is cooking, add vegetables to boiling water and cook 2 to 3 minutes, or until just tender. Transfer vegetables with a slotted spoon to a colander to drain and keep water at a boil.
Add vegetables, garlic, and salt to taste to bacon and sauté until cauliflower is pale golden, about 3 minutes. Keep mixture warm.
Cook pasta in boiling water until al dente and drain well in colander. Add pasta, remaining 3 1/2 tablespoons oil, and salt and pepper to taste to cauliflower mixture and toss until combined well.
Sprinkle pasta with bread crumbs and serve with Parmesan.
Adapted from Gourmet, January 1996