Dice the onion and carrot and add to a heavy bottomed frying pan along with the olive oil and a good pinch of salt.
Fry for around 5-10 minutes, stirring regularly, until the onions are translucent and the carrots are just starting to soften.
De-seed and dice the pepper, then add to the pan along with the vegan chorizo (either diced or crumbled) for a further 5 minutes.
Stir through the minced garlic, paprika, tomato purée and the rice. Stir for a couple of minutes so it starts to absorb all of the flavours.
Add the saffron to the pan and then pour in a quarter of the stock. Stir well then bring the stock to a boil. Turn the heat down so the stock is just at a simmer and let the rice absorb all of the stock before adding the next quarter, keep repeating this until you've added the final stock.
To make the scallops
Cut the stems of your king oyster mushrooms into 3 or 4 pieces, roughly the size of a scallop (e.g. 1 -1.5 inches).
In a shallow bowl, mix together the warm water, miso paste, “fish” sauce, soy sauce and sea weed flakes.
Submerge the “scallop” pieces in this broth and leave to sit for at least 30 minutes. You can continue making the rest of the dish in this time.
Remove the mushroom “scallops” from their broth and add to a frying pan pan.
Turn the heat to high and let the scallops cook for 3 – 5 minutes or until they are cooked through and their bottoms have caramelised.
Turn-over and cook for another 3-5 minutes on this side.
To finish the paella
Stir in the diced tomato, peas and black olives, replace the lid, and cook for a further 5 minutes, or until hot through.
Add the scallops to the dish, then scatter over fresh parsley leaves.