Peel the mushrooms and remove the stalks. Finely chop the onion and fry in 1 tbsp oil until see through. Finely shred the spinach and add to the onion for a few minutes until wilted. Spread the inside of the mushrooms with sun-dried tomato paste and put the spinach mixture on top. Cook in a 180 degree oven for 20 minutes. Once cooked you may like to put a bit of vegan cheese on top and pop under the grill until melted or golden brown.
