Firstly add the anchovies to a pan and stir until these reduce into a stock on a medium heat.
Add the red pepper, paella rice, chilli flakes, chopped tomatoes, paprika, peas or green beans and top with the lemon (quartered), and gradually add the boiling water.
Leave to simmer for 15 minutes, stirring occasionally or until the rice is cooked.
Add the seafood (prawns, mussels and clams) and stir well.
Continue cooking until the mussels and clams open, and the prawns are pink in colour. This should take approximately 4 minutes.
Sprinkle with chopped parsley and serve.