Chicken Poppyseed Casserole

I made this for a few guests last week... it's quick, tastes like food your grandma would serve, and is great if you have a picky-ish eater (or kids or guys). I know that poppy seeds are something you may not have in the pantry, but they're worth buying for this recipe and for poppy seed muffins or homemade vinegarette dressing. Trust me. You can find them with the spices in the baking aisle. By the way, from here out I'll put ( ) around optional items or personal notes, typically lighter options for ingredients.

Chicken Poppy seed Casserole
For casserole:
4 lbs. chicken breast (I used 4 lg. breasts for about 6 servings total)
2 cans cream of chicken soup (reduced fat or low-sodium)
8 oz. sour cream (light)
1 sleeve Ritz crackers, crushed (multi-grain or reduced sodium)
For toping:
1/2 stick butter (light)
1 T poppy seeds
1 sleeve Ritz crackers, crushed

Preheat oven to 350 degrees
Boil chicken breasts and cut cooked chicken into ~1" pieces.
Coat casserole dish wish non-stick spray and add chicken.
Add soup, sour cream and one sleeve of crushed Ritz to the chicken and mix. Spread mixture evenly in casserole dish.
In a small saucepan, melt butter. Add poppy seeds and second sleeve crushed Ritz to pan and mix.
Spread poppy seed topping over chicken.
Bake at 350 for 30 minutes.