While pasta is boiling, heat oil over medium-high heat in a large skillet. Season chicken with salt and pepper; cook until opaque throughout, 3 to 5 minutes per side. Halve each piece lengthwise, then thinly slice crosswise. While chicken pan is still hot, toss the mushrooms in and saute until golden brown (3-4 minutes). Use a little extra olive oil if needed.

In a 5-quart heavy pot, melt butter over medium. Add flour and garlic; cook, whisking, 1 minute. While whisking constantly, gradually add milk; bring to a simmer. Keep whisking frequently as sauce thickens, about 1 minute more. Add mushrooms and tomatoes; cook 1 minute. take the pan off the heat and and gradually stir in Provolone and 1/2 cup Parmesan.

Add chicken and pasta to pot; season with salt and pepper to taste. Divide pasta mixture between baking dishes. If freezing, place remaining Parmesan cheese in a zip-top baggie. If cooking, sprinkle on top. Bake, uncovered, until top is golden and bubbling, about 25 minutes. Let stand 5 minutes before serving.

Freezer Instructions:
To freeze, prepare as above then let pasta cool. Cover pan well with plastic wrap. Place extra cheese in baggie (for topping) on top and then cover entire pan well with foil. Freeze for up to 3 months. to bake, preheat oven to 400. Remove foil and plastic from pan and set cheese baggie aside. Place foil back on pan and bake for about 1 1/2 hours. Remove foil, stir pasta, and top with cheese. Return pan to oven and bake for an additional 15 minutes or until mixture is hot and bubbly throughout.