Cook the mushrooms in a non-stick frying pan (skillet) without any oil.
Keep stirring briskly for about 10 minutes until all the moisture has evaporated from the mushrooms.
Put the onion, vegetables and nuts in a food processor or blender and process until they bind together and form a thick mixture.
Transfer to a bowl, season with salt and stir in the yeast extract, coriander and breadcrumbs.
With damp hands, roll the mixture into 8 balls and flatten to make round patties.
Spread the breadcrumbs out on a plate and roll each patty in the breadcrumbs until coated.
Heat the oil in a non-stick frying pan (skillet).
Working in batches, cook the patties for about 5 minutes, or until crisp and golden brown on both sides.
Remove from the pan and keep warm in a low oven while you cook the rest.
Serve with onion rings and cherry tomatoes.