Preheat the oven to 200°C.
Put the meatball ingredients into a blender and pulse until well combined. Season with salt and pepper, then knead it through. Form 12- 15 little balls, put these on a lined baking sheet and bake for 25 minutes.
Meanwhile, put the mushrooms in a ovenproof dish, add the garlic and drizzle with oil. Bake for 10 minutes in the oven.
Take the mushrooms out of the oven add the double cream and sherry and gently cook on the stove until you get a thick sauce. Stir in the parsley.
Serve the meatballs with the mushroom sauce poured over them.