Cheesey Broccoli chicken

This came from my mother-in-law,she made it for her kids growing up and it's very rich and filling

4-6 boneless.,skinless breasts
1 can broccoli cheese soup (you can use fat free if you like)
1/4 C milk(mix with soup) 2 % is fine
1 onion chopped
2 TBSP butter
1 C frozen broccoli florets

Melt butter over med heat in an electric skillet or on the stove,add onion and saute for 6-7 minutes. Add chicken and sear on both sides. Top with soup mixture and cook covered for 20 min till chicken is well done. Add broccoli and cover for an additional 10 min.
I top with some seasoned bread crumbs before serving.