Cook noodles according to package directions. Drain.
8 ounces wide egg noodles
Heat a large skillet over medium heat. Put oil in the pan and cook the onion and carrot for about 6 minutes or until carrot is almost tender, stirring occasionally. Sprinkle with flour and cook 1 minute, stirring constantly. Gradually whisk in milk, raise heat to medium-high and cook for 5 minutes, stirring constantly with a whisk until slightly thick.
2 tablespoons olive oil, 1/2 cup yellow onion, 1/3 cup carrot, 2 tablespoons flour, 2 3/4 cups milk
Stir in cream cheese, mustard, salt, and pepper and cook 2 minutes, stirring constantly.
4 ounces cream cheese, 1 tablespoon Dijon mustard, 1/4 teaspoon salt, 1/2 teaspoon black pepper
Preheat broiler.
Reduce heat to medium, stir in peas, corn, 1/4 cup Parmesan cheese, and tuna. Add pasta and heat through. Top with remaining 1/4 cup Parmesan cheese.
1/2 cup frozen peas, 1/2 cup frozen corn, 1/2 cup grated Parmesan cheese, 2 cans tuna
Broil 3 minutes or until golden and bubbly. Let stand 5 minutes before serving.