Pound pheasant breasts under a layer of plastic wrap using a meat tenderizer mallet or hammer.
Salt pheasant and set aside.
Heat butter and olive oil in large pan over medium heat until butter bubbles. Add garlic and reduce heat.
Place flour on a plate or in a bowl. Dredge pheasant in flour until breasts are covered.
Add pheasant cutlets and fry on medium heat 2-3 minutes. Turn over and cook another 1-2 minutes.
Remove pheasant from pan.
On high heat, add mushrooms and sauté for 3-4 minutes. Add Marsala, rosemary and chicken stock. Boil until sauce thickens, for 2-4 minutes. Add salt and pepper to taste.
Return pheasant to pan, coat both sides with sauce and serve.
