Preheat the oven to 400°F and prepare a large oven-safe cast iron skillet.
Wipe the cremini mushrooms clean and slice them into thick, meaty halves.
Snap the woody ends off the asparagus and mince the garlic cloves finely.
Season the chicken breast evenly with sea salt and cracked black pepper.
Melt the ghee in the skillet over medium-high heat until shimmering.
Sear the chicken for 3 minutes per side to develop a golden crust, then move to the side of the pan.
Toss in the mushrooms, asparagus, garlic, thyme, and rosemary, stirring to coat in the herb butter.
Place the skillet in the oven and roast for 12 minutes or until the chicken is juicy and cooked through.
Let the meat rest for 5 minutes before serving to allow the flavors to meld.