1 tbspolive oil70 gmbutter, coarsely chopped2garlic cloves, finely chopped6large field mushrooms, coarsely chopped1 tbspplain flour500 ml(2 cups) chicken stock80 mlmanzanilla sherry60 gm(¼ cup) double cream50 gm eachchestnut mushrooms and thickly sliced king brown mushroomsTo serve:crème fraîche
Heat olive oil and 50gm butter in a saucepan over high heat until butter is foaming. Add garlic and field mushrooms and stir continuously until mushrooms are just golden and tender (5-10 minutes). Add flour and stir for 1 minute, add stock and sherry and cook until mushrooms are very tender (15-20 minutes). Add cream and process in a blender until smooth. Season to taste.
Meanwhile, heat remaining butter in a large frying pan over high heat until foaming, add chestnut and king brown mushrooms and cook until golden and tender (3-5 minutes). Serve soup hot, topped with crème fraîche and sautéed mushrooms.