Cook pasta according to package instructions in lightly salted water.
In a large pan, over medium heat, melt the butter. Add the mushrooms and cook 3-5 minutes. Add in the celery and onions and cook until the vegetables are soft and translucent.
Stir in the flour. Slowly stir in the broth and 1/4 cup of the milk. Simmer until the sauce thickens up, about 5-8 minutes. Turn off the heat and let cool at least 10 minutes before stirring in the Greek yogurt.
Preheat the oven to 350 degrees and arrange 5 oven safe containers on a cookie sheet. Spray lightly with some cooking oil.
In a microwave safe bowl (I just used one of the meal prep bowls) cook the diced carrots and 2 tablespoons of water for 3 minutes, or until soft.
Add the carrots, peas, cooked noodles, 1/2 cup of milk, and tuna to the roux. Stir well and evenly distribute amongst the 5 bowls. Top each bowl with some of the shredded cheese.
Bake in the oven for 20 minutes.
Let cool before covering with lids and placing in the refrigerator. Reheat in the microwave for 2-3 minutes.
Notes
You can skip making your own roux and instead use 1 can of cream of mushroom soup. Use the cream of mushroom soup along with the celery, carrots, peas and milk. Leave out the butter, flour, mushrooms, and broth.
These freeze fine, just let them defrost well before reheating and stirring so the noodles keep their shape.
Find in the MyFitnessPal and MacrosFirst apps by searching Stay Fit Mom Tuna Casseroles