- Preheat the oven to 190° C / gas 5. Scrub the mussels really well and remove the beards. Discard any with damaged shells and those that don’t shut tight when tapped on the edge of the sink. Rinse well.
- Put all the mussels in a saucepan and cover with a tight-fitting lid. Place over a high heat and cook for 2 mins, shaking the pan halfway, until all the shells have steamed open but the mussels are only just cooked. Discard any that don’t open. Tip into a colander over a bowl and save the liquid.
- Once cooled slightly, remove the mussels from their shells and reserve 40 half-shells ready to serve. Chop the mussels then set aside.
- Add oil to a pan, add the onion and red pepper and cook over a medium heat for 5 minutes. Add the garlic and cook for a further 2 minutes, stirring regularly until soft.
- Add the liquid from the mussels and cook 4-5 minutes, stirring regularly until the liquid almost completely evaporates, then remove from heat.
- Stir in the chopped mussels, peas, parsley, black pepper and 30g of breadcrumbs.
- Stuff each mussel with some of the mixture, mounding into the shell. Mix the remaining breadcrumbs and parmesan together and press a little into the top of each mussel, scattering the rest over the stuffed mussels.
- Arrange on a baking tray and bake 15 minutes until the stuffing is a pale golden brown and the mussels are hot. Transfer the shells to your serving plate and eat immediately.
- You could prepare the vegetables for the stuffing in advance and just add the mussels before baking.