Combine the flour, salt, pepper, and oregano in a shallow dish.
Dredge the chicken breasts in the mixture, ensuring they are well-coated.
Shake off any excess flour for best results.
Heat the butter and olive oil in a large skillet over medium heat.
Once the butter is melted and bubbling lightly, add the chicken breasts.
Cook each side for about 3 to 4 minutes until they turn golden brown.
Remove the chicken from the skillet and place it on a plate lined with paper towels.
In the same skillet, add the sliced mushrooms and sauté them until tender and fragrant.
This should take about 3 minutes.
Pour in the Marsala wine and chicken broth to deglaze the pan.
Allow the mixture to cook for an additional 2 to 3 minutes, stirring occasionally.
This will help create a rich sauce full of flavor.
Return the chicken breasts to the skillet.
Let them simmer in the sauce for about 10 to 15 minutes.
Ensure the chicken is cooked thoroughly and the sauce thickens to your liking.