In a baking dish, coat mushrooms thoroughly with oil and spice. Make sure they can fit in a single layer and turn them so they are all underside up.
Place in the oven for 25 minutes and when nicely roasted, set aside to cool.
In a small saucepan, melt butter. Stir in garlic and parsley and allow to cook for about a minute before removing from heat.
Decorate your plate/s with rocket or parsley, if using. Place mushrooms, making sure they are still underside up, pour over the garlic butter, adding a small dollop of crème fraîche on each, a thin slice of preserved lemon and cracked pepper over the top.
Create a vegan version of this recipe by using a vegan cream cheese replacement and olive oil instead of butter.