Mushroom and Époisses Pithiviers - Pong Cheese

Ingredients

• Drizzle of olive oil
• 2 large, flat mushrooms (about 70g each), stalks trimmed
• 30g butter
• 150g mixed mushrooms, such as chestnut, flat, button or portobello, very finely chopped
• 1 large banana shallot (or 2 round shallots), very finely chopped
• 1 fat garlic clove, crushed
• 70ml Madeira
• 1 tsp sherry vinegar
• 5-6 fresh sage leaves, shredded
• 100g époisses, half cut into small chunks, half sliced
• Flour to dust
• 500g block all-butter puff pastry
• 1 free-range egg, beaten, to glaze