1. Preheat oven to 450°.
2. Pierce sausage several times with a knife. Combine sausage, cauliflower, and 1 tablespoon oil in a small roasting pan; toss. Sprinkle evenly with 1/4 teaspoon salt. Bake at 450° for 15 minutes. Add garlic to pan; toss. Bake an additional 5 minutes or until sausage is done. Let stand 5 minutes. Cut sausage crosswise into 1/4-inch-thick slices.
3. Cook pasta according to package directions, omitting salt and fat; drain, reserving 2 tablespoons pasta cooking water. Combine pasta, reserved cooking water, remaining 1 tablespoon oil, remaining 1/4 teaspoon salt, and crushed red pepper in a large bowl; toss. Add cauliflower mixture, sausage, and cheese; toss gently to combine. Sprinkle with black pepper.