1. Heat 3 tablespoons of olive oil in a large, wide saucepan with a tight-fitting lid over a medium heat. Add the onion and garlic and sauté for five minutes, until soft.

2. Increase the heat to high, then add the mussels, wine and saffron with its soaking liquid, and cover with the lid. (If your pan isn't quite big enough to fit all the mussels comfortably, you may need to cook them in two batches, which is fine.)

3. Cook, shaking frequently, for two-three minutes, until the mussels begin to open. Remove from the heat and strain the mussels into a sieve placed over a bowl. (If you're cooking the mussels in two batches, simply scoop the first batch of cooked mussels out with a strainer and set aside while you cook the rest.) Strain the mussel broth through a fine sieve, and discard any gritty bits.

4. Season the prawns with sea salt. Heat the remaining oil in a heavy-based, deep-sided frying pan over medium-high heat. Add the prawns and flash-fry until the prawns are opaque on the outside but still translucent in the middle (about 30 seconds a side for large).

5. Add the mussel broth and bring to a simmer. Add the butter and mussels and gently stir through; the prawns should be just cooked. Sprinkle the stew with the baby red sorrel or parsley and add a grind of white pepper.

6. To serve, place the pan on the table, or serve in one big bowl, with a ladle and bowls for everyone. Serve with crusty bread. 

Suggestion: Sreve with Neil Perry's 'pan-fried snapper with Sicilian salsa'