Press sauté function; select custom. Press timer and set to 25 minutes. When inner pot is hot, add 1 tablespoon of the butter. Season the chicken well on both sides with salt and pepper. Add the chicken thighs to the inner pot (in batches) and cook until browned on the skin side, about 5 minutes. Transfer to a plate; set aside.

Add 3 of the remaining tablespoons of the butter to the pressure cooker and add the onion and thyme sprigs. Cook until onions are softened, about 3 minutes. Add the mushrooms and cook until softened and lightly golden. Add the garlic, season with salt and pepper, and cook until fragrant. Add the flour and cook, stirring, for 2 minutes. Add the marsala and cook, scraping the bottom of the inner pot to release any browned bits. Add the chicken stock and return the chicken pieces to the inner pot. Cancel any remaining time. Lock the lid. Press pressure function; select poultry setting on medium. Press timer; select 12 minutes.

Let the pressure release naturally for 5 minutes, then quick release any remaining pressure. Remove lid and transfer the chicken to a serving dish. Press sauté function; select poultry setting. Press timer; set to 5 minutes. Cook, stirring as needed, until sauce is thickened to the desired consistency. Adjust the seasoning if necessary and whisk in the remaining 2 tablespoons of butter. Spoon the sauce over the pasta and garnish with fresh thyme leaves.

Note:  This recipe was created specifically for the Emeril Lagasse Pressure AirFryer by Tristar. As such, cook times and temperatures may need to be adjusted if you would like to make this recipe in another pressure cooker.