Heat butter and olive oil in a wide oven-safe skillet over medium. Add the onions with a pinch of salt and let them soften, stirring every few minutes until golden and sweet, about 20 to 25 minutes.

Stir in garlic for a minute. If using wine, deglaze the pan with a splash, scraping up the browned bits.

Push the onions to the sides, add the chicken to the center, and season with salt and pepper. Cook until the chicken is just losing its pink, about 4 to 5 minutes.

Pour in the orzo, thyme, and Worcestershire. Stir to coat the orzo. Add the warm broths and cream. Taste the mixture and adjust seasoning.

Sprinkle half the cheese into the skillet and fold it in. Top with the remaining cheese.

Transfer the skillet to a preheated 375°F oven and bake uncovered for 18 to 22 minutes, until the orzo is tender and the top is bubbly. Broil for an additional 1 to 2 minutes for extra color if desired.

Let it rest for 5 to 10 minutes before serving. Garnish with parsley if desired.