Heat a large, deep frying pan over a medium-high heat.
Cook the chorizo for a few minutes until it releases some of its own oils and begins to brown.
Add the onion and cook until tender.
If the chorizo is not very fatty - add a little drizzle of olive oil.
Add the mushrooms and cook until lightly golden.
Add the garlic, celery, peppers, chilli, paprika and cumin.
Season well with salt and pepper.
Cook until fragrant.
Add the rice and mix it in well to coat with all the spices and vegetables.
Add the stock, bay leaves and tomatoes.
Bring to the boil, then reduce to a simmer.
Cover and cook for ± 12 minutes until the rice is just tender.
Add the prawns, and gently stir them through the rice.
Cover again and cook for a further 4–5 minutes until they turn pink and are cooked through.