Chicken and mushroom tortellini bake

First of all, I need to thank you ladies for providing my family with food and desserts. This blog is always my first online recipe resource, and you never fail me! In fact, as we speak, I'm making my husband's birthday cake with this recipe. So thanks!

And now for the recipe. I made the "Chicken Tortellini Casserole" from Stephanie's awesome gift that keeps on giving, the Tried and True Recipe book (page 51) for the first time last night. Of course I made some adjustments, which is why I'm posting the recipe here, but it was surprisingly tastier than I had even hoped.

This recipe serves 2 with 2 leftovers-servings (which to me are smaller than normal servings--is that crazy?).

Cook and cut about 2 chicken breasts into small pieces. (One breast if it's big enough will do.)
Cook about a 1/2 lb. of tortellini pasta according to the package directions. (Mine was frozen and boiled for about 7 minutes.)
Place chicken, tortellini and a 4oz can of mushrooms in a bowl . Reserve about half of the mushroom juice, but you don't need the rest.
Make a white sauce: Melt 2 Tb butter in a saucepan. Add 2 Tb flour and whisk until blended. Remove from heat and add about 3/4 cup milk plus the reserved mushroom juice. Whisk until smooth. Continue to stir over medium-low heat until the sauce thickens slightly.
Add to the sauce:
a couple of chopped green onions
1/2 cup sour cream
2-4 ounces of shredded mozzarella cheese
1-2 Tbs melted butter (Probably totally unnecessary...)
Spread some sauce on the bottom of a casserole dish. Add the chicken, pasta and mushrooms. Add the rest of the sauce and more cheese if you'd like.
Bake @ 350 for about 25 minutes, or until thoroughly heated.

(Next time I want to add some chopped spinach or maybe broccoli.)