Trim pork; sprinkle with half each of the salt and pepper. Dredge in all but 1 tsp of the flour
In large skillet, heat oil over medium-high heat; cook pork, in batches and turning once, until just a hint of pink remains inside and juices run clear when pork is pierced, about 5 minutes.
Transfer to plate.
Saute shallot and garlic until softened, about 2 minutes.
Add mushrooms, Italian seasoning and remaining salt and pepper; sauté, stirring until golden, about 5 minutes.
Add Marsala; cook until reduced by half.
Add broth and ¼ cup water; reduce heat and simmer until reduced by half, about 2 minutes.
Meanwhile, mash butter with remaining tsp flour; stir into sauce and cook until thickened.
Return pork to pan; heat through.
Sprinkle with parsley.
