Heat the oil in a paella pan, add the onion and cook for 5 minutes until it starts to soften. Add the garlic, red pepper and tomatoes and cook for a further minute.
Increase the heat and add the rice, stir and cook for 1 minute. Add the wine and continue cooking for 2-3 minutes or until the wine has evaporated.
Add the saffron, paprika and stock, bring to the boil, reduce the heat to low and simmer uncovered for about 15 minutes. If the mixture is drying out and the rice is not cooked then add more stock.
Before the rice is fully cooked, add the frozen peas and after 1 minute add the chopped smoked haddock and langoustine tails (or your own choice of seafood) and gently push in to the rice. Try not to stir.
Once the seafood is cooked, add the lemon juice and scatter with freshly chopped herbs. Serve with wedges of lemon on the side.