Begin by cutting the chicken breasts in half lengthwise to create thinner cutlets. Season both sides generously with salt and pepper, then dredge each piece in flour, ensuring an even coating.

In a large skillet, heat 2 tablespoons of olive oil over medium-high heat until shimmering. Carefully add the dredged chicken cutlets and cook for about 4-5 minutes on each side, or until they develop a beautiful golden-brown crust. Remove them from the skillet and set aside.

In the same skillet, reduce the heat to medium and add 2 tablespoons of butter. Once melted, stir in sliced mushrooms along with 1 teaspoon of Italian seasoning. Sauté for 5-6 minutes until they're nicely browned.

Add 3 minced garlic cloves to the skillet, cooking for about 30 seconds until fragrant. Pour in 1 cup of chicken broth, 2 tablespoons of freshly squeezed lemon juice, and 1 tablespoon of Dijon mustard. Let this mixture simmer for 3-4 minutes.

Pour in 1 cup of heavy whipping cream and bring the mixture back to a gentle simmer. Return the sautéed chicken and mushrooms to the skillet, coating them generously in the creamy sauce. Let it bubble for an additional 5 minutes.

Taste the sauce and adjust the seasoning with extra salt and pepper as needed, then serve immediately.