Cooking Instructions

• Melt 2 tablespoons unsalted butter in a 12-inch cast iron skillet over medium heat. Add sliced yellow onions, fresh thyme leaves, 1 teaspoon kosher salt, and black pepper. Cook until the onions have reduced by over half and are very soft and deep golden-brown, 32 to 36 minutes.
• Pour in ¼ cup dry white wine and scrape up any browned bits on the bottom of the skillet. Stir until the wine is evaporated. Transfer the onions to a plate.
• Add 1 cup long-grain white rice to the skillet and cook, stirring occasionally, until it smells toasty, about 1 minute. Stir in low-sodium chicken broth, whole milk, and the remaining 1 teaspoon kosher salt. Bring to a boil, then reduce heat to medium-low, cover, and cook for 5 minutes.
• Stir in the bite-size pieces of boneless chicken so that it is evenly distributed in the rice. Cover and simmer, stirring occasionally, until the rice is tender and chicken is cooked through, 10 to 12 minutes.
• Stir the caramelized onions and 3 ounces of shredded Gruyère cheese into the rice. Taste and season with more kosher salt and black pepper as needed. Sprinkle evenly with the remaining 3 ounces Gruyère. Transfer the skillet to the oven and broil until the cheese turns golden-brown in spots, 3 to 4 minutes.
• Serve garnished with more fresh thyme leaves and black pepper if desired.