Preheat the oven to 350F.
Heat 1 T olive oil in oven friendly pot. Season the chicken with salt and pepper.
Sear each side of the chicken on high for about 1 minute.
Add the onion and shallot to the pot and cook until fragrant, about 1-2 minutes.
Add the garlic and cook until fragrant, about 1 minute.
Deglazed the pan with 1/4 cup whiskey and cook until almost dry.
Add the red wine and rosemary and bring to a boil.
Add the chicken stock, cover pot and transfer to the 350F oven. Poach chicken for about 1 hour, adding the mushrooms for the last 15 minutes.
Strain the pot and reserve 2 c of the remaining liquid for the sauce.
Melt 2 T butter in a small saucepan. Add the flour and stir to form a roux.
Whisk in the 2 c of reserved cooking liquid and bring to a boil. Cook until thickened.
Serve chicken, onion and mushroom mixture over gnocchi. Top with sauce and fresh arugula to serve.