Pound chicken to about ¼ inch between 2 pieces of wax paper. NOTE: It’s mainly the thickest part that needs flattening. This evens out the thickness for even cooking
Season chicken breasts generously with salt and pepper on both sides. Dredge them in flour and shake off excess
Preheat pan over medium-high heat, melt the butter with the olive oil. Add the garlic and saute briefly. Add the chicken breasts and saute 1 to 2 minutes on each side or just until very lightly browned. Remove and set aside
Add the mushrooms to the pan (Add more olive oil and butter if needed) and saute over medium heat for about 1 minute.
Return the chicken to the pan; stir in the lemon juice and wine and simmer, covered for 10 minutes or until chicken is done.
Add the capers and heat through. Put the chicken on a platter, spoon on the juices and garnish with parsley and lemon slices.