Chicken with Mornay sauce is a classic French dish that features tender chicken breasts smothered in a rich and creamy cheese sauce. The chicken is first seared to perfection, then topped with a decadent Mornay sauce made with Gruyere cheese, butter, flour, and milk. The dish is then baked until the cheese sauce is bubbly and golden brown. This elegant and flavorful dish is perfect for a special occasion or a fancy dinner party.