I made this tonight and my extremely picky 3 year old ate three helpings, so I'm posting it because it is solid gold! Use one slice of bread in a food processor to make about 3/4 cup of soft breadcrumbs.
- Preheat oven to 375 degrees.
- Prepare pasta according to directions. Rinse and set aside.
- In the meantime, mix breadcrumbs and 1Tbs butter. Set aside.
- Melt remaining 3Tbs butter in a medium saucepan over medium heat and add onion and carrots. Saute 4-5 minutes until softened.
- Add flour and stir while it bubbles. Cook one minute, stirring constantly.
- Add milk, water, mustard, salt and pepper, stirring while it thickens. Cook, stirring until it thickens to the correct consistency.
- Remove from heat and stir-in tuna.
- Mix in noodles and pour everything into a 1.5-2.2 quart glass pan. Crumble breadcrumbs on top.
- Cook, uncovered in oven for 20 minutes.