Step 1

Preheat oven to 400 degrees.

Step 2

Melt butter in a large oven-proof skillet over medium heat. Add the onions and cook for about 20-25 minutes, or until onions are golden and beginning to caramelize.

Step 3

Stir in the cognac and white wine. Bring the mixture to a boil and then reduce to a simmer. Simmer for 2-3 minutes until the alcohol is cooked off and slightly reduced. Stir in flour. Cook for 1 minute.

Step 4

Slowly whisk in beef broth. Add salt, sugar, pepper and thyme sprigs. Bring to a boil and reduce to a simmer. Simmer for 3-4 minutes until slightly thickened. Then remove from skillet and set aside. Remove thyme sprigs.

Step 5

Season chicken breasts with salt and pepper.

Step 6

Heat oil in the now empty skillet over medium-high heat. Once oil is hot, add chicken breasts and cook about 3-4 minutes per side, until golden. Return onions to skillet and sprinkle cheese over the chicken. Bake for 8-10 minutes until chicken is cooked through and cheese is melted.

Step 7

Spoon some of the onions and gravy over the top of the chicken, garnish with fresh chopped parsley, and serve.