Chicken Marsala

Why I Love This Recipe
I found this recipe for chicken marsala from Cook's Illustrated a few years back. Over the years, I've made some adjustments. I think I've got it down to just about perfect now. If you like a thicker sauce, mix a a couple of teaspoons of cornstarch with cold water, and add that to the sauce after you melt in the butter. Serve atop a bed of fettucine, with a side of fresh sauteed green beans. Absolutely delicious! Recipe can easily be halved by just using 2 chicken breasts instead of 4. I'd reccomend using the same amount of sauce though. Enjoy!
Ingredients You'll Need
4 boneless, skinless chicken breasts
1 cup unbleached all-purpose flour
kosher salt
ground black pepper
2 tablespoons olive oil
4 slices of bacon or pancetta, chopped
2 cups white or cremini mushrooms
2 large garlic cloves, minced (about 1 tbsp.)
1 tbsp. minced shallot
1 tbsp. tomato paste
1 1/2 cups marsala wine (sweet)
1 1/2 tbsp. fresh lemon juice (1 small lemon)
4 tbsp. unsalted butter cut into 4
pieces, room temperature
2 tbsp. chopped fresh parsley leaves
Directions
Adjust oven rack to lower-middle position, place large heatproof dinner plate on oven rack, and heat oven to 200 degrees.
Heat 12-inch heavy-bottomed skillet over medium-high heat until very hot (you can hold your hand 2 inches above pan surface for 3 to 4 seconds), about 3 minutes.
Pat chicken breasts dry.
Meanwhile, place flour in shallow baking dish or pie plate.
Season both sides of chicken cutlets with salt and pepper; working one piece at a time, coat both sides with flour.
Lift breast from tapered end and shake to remove excess flour; set aside.
Add oil to hot skillet and heat until shimmering.
Place floured cutlets in single layer in skillet and cook until golden brown, about 3 minutes.
Using tongs, flip cutlets and cook on second side until golden brown and meat feels firm when pressed with finger, about 3 minutes longer.
Transfer chicken to heated plate and return plate to oven.
Return skillet to low heat and add pancetta; saute, stirring occasionally and scraping pan bottom to loosen browned bits until pancetta is brown and crisp, about 4 minutes.
With slotted spoon, transfer pancetta to paper towel--lined plate.
Add mushrooms and increase heat to medium-high; saute, stirring occasionally and scraping pan bottom, until liquid released by mushrooms evaporates and mushrooms begin to brown, about 8 minutes.
Add garlic and shallot Saute for 1 minute.
Add cooked pancetta and tomato paste.
Stir whil sauteeing, until tomato paste begins to brown, about 1 minute.
Off heat, add Marsala; return pan to high heat and simmer vigorously, scraping browned bits from pan bottom, until sauce is slightly syrupy and reduced to about 1 1/4 cups, about 5 minutes.
Off heat, add lemon juice and any accumulated juices from chicken; whisk in butter 1 tablespoon at a time.
Season to taste with salt and pepper, and stir in parsley.
Pour sauce over chicken and serve immediately.