This is a very good basic pasta recipe, especially if you like garlic (as we do!). To serve it still piping hot from the stove, you can time the cooking steps so that the pasta is cooking and the vegetables are sautéing during the last portion of time that the garlic is roasting in the oven.
Lightly spray each head of garlic with cooking spray. Wrap each garlic head separately in foil. Place garlic in a small baking pan. Bake at 400° for 45 minutes. Cool 10 minutes.
Separate garlic cloves. Squeeze cloves to extract the pulp; discard peels.
Place garlic pulp, mustard, lemon juice and pepper in food processor or blender container; cover. Process until pureed; set aside. (I have also done this by hand once while we were in the process of moving and I couldn't find my food processor, and it worked just fine. It's tedious, but it does work out OK.).
Cook and stir zucchini and mushrooms in hot oil in a large skillet on medium-high heat for 3 minutes or until zucchini is tender-crisp. Add the pureed garlic mixture, water and tomato; mix well. Reduce heat to low; cook until thoroughly heated, stirring frequently.
Toss the vegetable mixture with hot cooked pasta, and serve while still warm.