Preheat oven to 400°.
Heat olive oil in a large nonstick skillet over medium heat. Add onion, carrot, and celery; cook 10 minutes or until onion is tender, stirring frequently. Add garlic; cook for 1 minute, stirring constantly. Add sun-dried tomatoes, thyme, crushed red pepper, and diced tomatoes; cook 25 minutes or until thickened, stirring occasionally.
Combine 1 cup Romano, ricotta, parsley, and egg white in a bowl.
Cook pasta according to package directions, omitting salt and fat. Drain; return pasta to pan. Add ricotta mixture to pan, stirring to coat. Add tomato mixture and provolone, tossing just until combined (do not overstir). Spoon pasta mixture into a 13 x 9-inch baking dish coated with cooking spray. Sprinkle with remaining 1/2 cup Romano. Bake at 400° for 25 minutes or until bubbly and top is browned.
Wine note: Here's one of the best-kept secrets in food and wine pairing: Cheese often works better with white wine than red. As proof, try this delicious cheesy baked pasta casserole with a crisp white such as pinot grigio, and watch how the wine's zesty acidity cuts through the richness of the cheeses. A favorite: Bollini Pinot Grigio from Italy. The 2004 is $10. -Karen MacNeil