Cut chicken breasts into large chunks. Using large frying pan, brown chunks in olive oil - don't cook completely through. Once chunks are browned, add white wine to pan and simmer chunks until cooked completely. Let cool. This can be done the day before and refrigerate chicken.
Preheat oven to 350. Spray a 9x9 x3" deep (or 3-4-qt) casserole with cooking spray.
Mix cream of mushroom soup & sour cream together, then mix in chicken chunks. Place mixture in pan.
Mix stuffing mix and chicken broth according to package directions (on either stovetop or in microwave) and let sit for 5 minutes. Spread or sprinkle across top of filling mixture. (Or you can actually refrigerate it at this point overnight and cook the next day).
Bake at 350 for 35 - 45 minutes until heated through; the topping browns lightly, and the sauce bubbles around edge.
This was a recipe from a friend that my husband & I modified slightly. It's delicious.