1 tablespoon olive oil
500g fresh mushrooms, sliced
1 large onion, minced
30g brown breadcrumbs
2 tablespoons vegetarian oyster or mushroom sauce
1 egg
Salt and freshly ground black pepper 

Heat 1/2 the oil a large frying pan over medium heat. Add mushrooms and onions; cook and stir for about 4 minutes until the mushrooms begin to give up their juices. Stir in bread cubes and oyster or mushroom sauce then cook and stir for 1 minute. Remove mixture from pan and set aside to cool. Wipe pan clean. Beat egg and add it to the mushroom mixture. Season to preferred taste with salt and pepper. Add the remaining oil to frying pan and place over medium heat. Spoon mixture into frying pan in 4 equal amounts. Once brown on one side, flip over, and allow the other side to turn brown, turning down the heat to prevent them from burning. Place on plate with kitchen paper to absorb any excess oil.