Directions

1. 1

   Heat the olive oil in a large heavy Dutch oven over medium-high heat. Pat the chicken breasts dry and season both sides generously with kosher salt and freshly ground black pepper. Once the oil is shimmering, carefully place the chicken breasts in the pot. Sear for 6–8 minutes on the first side until golden brown, then flip and sear the other side for another 6–7 minutes until deeply browned. Transfer the cooked chicken to a clean plate and set aside.

2. 2

   In the same pot, add the sliced leeks and minced onion. Sauté over medium heat, stirring occasionally, for about 8 minutes until the vegetables are softened and fragrant. Add the minced garlic and continue cooking for another 2 minutes until fragrant.

3. 3

   Pour in the chicken broth and dry white wine, stirring to deglaze the bottom of the pot and incorporate any browned bits. Whisk in the Dijon mustard until well combined, then stir in the minced fresh thyme. Bring the mixture to a simmer, then return the chicken breasts to the pot, nestling them among the vegetables and sauce. Cover with a lid and reduce the heat to medium-low. Simmer gently for about 15 minutes until the chicken is cooked through, reaching an internal temperature of 165°F at the thickest part.

4. 4

   Transfer the cooked chicken breasts to serving plates. Increase the heat to medium-high and bring the liquid remaining in the pot to a gentle boil. Cook uncovered for about 15 minutes, stirring occasionally, until the sauce has reduced and become glossy and thickened. Remove from heat and whisk in the unsalted butter. Taste and adjust the seasoning with additional salt and pepper as needed.

5. 5

   Spoon the reduced Dijon sauce generously over each chicken breast, making sure to include the softened leeks and onions. Garnish with fresh thyme leaves and serve immediately while hot.