Directions

1. In large pot of lightly salted boiling water, cook macaroni until tender, following package directions. Drain well. Return to pot.
2. Meanwhile, in large non-stick saucepan over medium heat, heat oil. Add scallions and salt. Cook, stirring, occasionally, 3 minutes. Gradually stir in flour. Cook 1 minute. Gradually stir in 1 cup of the milk until well blended, with no lumps. Gradually stir in remaining milk. Bring to a boil. Lower heat. Simmer, stirring, until lightly thickened, 2 to 3 minutes. Remove from heat. Stir in mustard. Stir in Cheddar, Monterey Jack and 1/4 cup of the Parmesan.
3. Preheat oven to 375°F (100°C). Lightly coat 33 x 22 x 5 cm (13 x 9 x 2 in.) baking dish with non-stick cooking spray.
4. Fold carrot and cheese sauce into macaroni. Scrape into prepared baking dish. Arrange tomatoes in single layer over top. Combine remaining 1/4 cup Parmesan and crumbs in small bowl. Sprinkle over tomatoes.
5. Bake until filling is bubbly and topping is lightly browned, about 20 minutes. Let stand 10 minutes before serving.

Cost for each person: approximately $1.25