In a medium bowl marinade lamb chops with olive oil, salt, pepper, garlic and minced rosemary. Rub it all over the meat, cover the bowl and put into fridge for at least 30 minutes.
In the meantime make sweet potato and parsnip puree. Peel and cut the onion, garlic, sweet potato and parsnip into pieces.
In a medium pot heat avocado oil over medium heat. Add onions and garlic. Stir and fry until translucent, for a few minutes. Add the sweet potatoes and parsnip and brown for another few minutes. Stir occasionally. Add chicken stock, cover with a lid and simmer for 20 minutes or until the root veggies are soft.
In the meantime prepare the ingredients for the mushroom chestnut gravy. Cut the crimini mushrooms in half and slice them up. Cut the portobello mushroom into the same size. Peel and dice onion, and mince garlic. Set everything aside.
Preheat oven to 350 degrees. Heat avocado oil in a large pan over medium/high heat. Sear the marinated lamb chops on high heat for 3 minutes each side. If the temperature is getting too high reduce to medium. Flip the lamb chops to the smaller sides as well and cook for a little bit until they are browned all around. Place the meat on a baking sheet and bake in the oven for about 10 minutes for medium rare. If you prefer it more cooked through bake it a little bit longer.
In the meantime prepare the gravy. Use the fat that is in the pan from frying the meat. Put the temperature on medium and add the onions and garlic. Fry for about a minute until translucent. Add the mushrooms and the broth and cook until the mushrooms are browned on both sides. Stir occasionally. Once the mushrooms are done add the chestnuts. Finally add the coconut creme, reduce temperature to medium/low. Season with salt and pepper to your liking.
Once the sauce is done the meat should be ready. Take it out of the oven and let it rest for about 5 minutes. In the meantime puree the sweet potato and parsnip mash. Season with salt and pepper to your liking.
Serve the lamb chop on top of the mash and add the mushroom and chestnut gravy.