Begin by butterflying the chicken breasts to ensure even cooking.
Melt butter in a large skillet over medium heat. Add minced garlic and fresh thyme, sautéing until fragrant.
Add the chicken breasts to the skillet and cook until they are golden brown on both sides, being careful not to cook them through completely.
In a separate saucepan, whisk flour over medium heat, then gradually add chicken broth, Parmesan cheese, and cream, stirring until smooth and slightly thickened.
In a mixing bowl, combine Dijon mustard, lemon juice, honey, black pepper, and salt to create a flavorful marinade.
Thoroughly coat each chicken breast in the marinade, ensuring an even covering.
Arrange the marinated chicken on a baking sheet lined with parchment paper.
Bake in a preheated oven at 400°F (200°C) for approximately 25 minutes, or until the chicken is fully cooked through.
Once cooked, drizzle the Parmesan sauce generously over the chicken. Garnish with fresh parsley leaves before serving.