A seaside barbecue is great fun and you can get a lot more inspiration from your local fishmonger's slab than from the usual selection of pre-packed sausages, burgers and kebabs in supermarkets. If you have ever eaten fantastic fresh fish by the sea in Italy, Greece or Spain, more often than not it's been cooked over charcoal. I've just recently bought a great portable barbecue, the Coleman Perfect Flow Grill Stove (£69.99), from the Dorset Leisure Centre in Charmouth (01297 560473). It runs on a small gas bottle and folds up neatly to pop in the boot of the car.

Lobster with modern Russian salad

Serves 4

When you barbecue lobster you're guaranteed that extra special "wow" factor. Russian salad is a bit of a thing of the past and always used to look like it had been made with frozen mixed vegetables. You can use whatever seasonal vegetables you have at hand for this recipe.

2 lobsters weighing about 500-600g each
Vegetable or corn oil for brushing
Sea salt and freshly ground black pepper
1 lemon, quartered, to serve

For the Russian salad

2-3 thick spears of asparagus, trimmed and cut into cm dice
12-14 green beans, trimmed and cut into cm pieces
2 medium carrots, peeled and cut into cm dice
5-6cm cucumber, halved lengthways, seeds scooped out and cut into cm dice
2 spring onions, chopped
6 large radishes, washed and cut into cm dice
4-5 medium-sized new potatoes, cooked in their skins, peeled and cut into cm dice
4-6tbsp good quality mayonnaise
1tbsp chopped chives
1tbsp chopped parsley

If you're using live lobsters for this recipe, kill them before boiling by rapidly cutting through the midline lengthways with a large sharp knife (this is what the RSPCA recommends, though many chefs prefer to freeze them first to send them to sleep). Cook the lobster for 2-3 minutes in boiling water, then drain and leave to cool.

Cook the asparagus, beans and carrots in boiling salted water for a minute, then drain and leave to cool. Mix with the rest of the ingredients and season to taste. With a heavy chopping knife, cut the lobster in half down the centre and crack the claws a few times with the back of the knife. Brush with oil, season and grill for about 5 minutes on each side. Serve with the lemon and the salad on the plate or separately.

Grilled vegetables with seafood

Serves 4-6

Grilling vegetables can bring out great unexpected flavours that you wouldn't normally get from, say, boiling or roasting. A lot of vegetables can be grilled from raw; the firmer vegetables will need a little boiling first or they will dry up before being cooked. Cook your carrots and fennel before you set off on your barbecue.

1 large bulb of fennel
3 medium-sized carrots
2-3 courgettes, cut lengthways into cm slices
2 red peppers, quartered and seeded
Sea salt and freshly ground black pepper
Vegetable or corn oil for brushing
500g mussels, cleaned and de-bearded
500g large cockles, washed and scrubbed
2 squid weighing about 150g, cleaned
6 large scallops, shucked and cleaned
6 large prawns, in the shell
5-6tbsp olive oil
A handful of green herbs such as fennel, chervil and flat-leaf parsley, washed

Cook the fennel in boiling salted water for about 10 minutes and the carrots a little less, depending on their size. Halve the fennel and cut into -1cm slices and the same for the carrots.

Preheat your barbecue and grill all of the vegetables for about 2-4 minutes on each side or until cooked. You will need to move the vegetables around the barbecue if they are beginning to burn – and depending on the heat of the barbecue. Once cooked, transfer to a serving dish, spoon over some of the oil and season.

You can either cook the mussels and cockles directly on the barbecue until they open, or take a pan with you and cook them in the pan with a lid on the barbecue until they open; then add to the vegetables. Cook the prawns for about 3-4 minutes on each side and add to the vegetables. Halve the squid tubes down the middle, then season with the scallops and tentacles, and cook for about 2 minutes on each side. Mix all of the fish together with the remaining oil and scatter over the herbs.

Squid with grilled red onions and vegetable salsa

Serves 4

I first had grilled onions in a Turkish restaurant in London's Stoke Newington, just sliced and simply grilled with sumac and pomegranate molasses. These are delicious and so simple – and perfect for the barbecue.

2 large red onions, peeled and cut into 1cm-thick slices
4 squid weighing about 150g, cleaned
Vegetable or corn oil for brushing
Sea salt and freshly ground black pepper

For the salsa

2 large shallots, peeled, halved and finely chopped
1tbsp white wine vinegar
a small cucumber, halved lengthways, seeds scooped out and cut into cm dice
1 small red pepper, halved, seeded and cut into cm dice
10 radishes, cut into small cm dice
1 small bulb of fennel, cut into cm dice
1tbsp green herbs (fennel, chervil, parsley), chopped
4-5tbsp olive oil

First make the salsa: bring the vinegar and shallots to the boil then transfer to a bowl and mix with all of the other ingredients. Preheat the barbecue, lightly brush the onions with oil and grill for about 3-4 minutes on each side on a medium heat; then transfer to a serving dish. Cut the squid tubes into 4 evenly sized pieces, season the tubes and tentacles and lightly oil, then cook briefly for just a couple of minutes on each side. Arrange on the onions and spoon the salsa over and around.

Grilled Plaice with Dukkah and radishes

Serves 4

Standard-sized plaice are not ideal for cooking on the barbecue as the flesh tends to be a bit soft, but if you manage to get your hands on a big, diver-caught plaice that can weigh 2-3 kgs you can treat it just like a brill or turbot. Great chunks of fish like this need simple preparation and I've seasoned the fish here with a nutty spice mix used in Middle Eastern cooking.

If you can't get hold of large plaice then you could use any firm-fleshed fish like brill, turbot, sea bream or John Dory. It's probably worth making a quantity of Dukkah and storing it in an airtight jar – it will keep for a month or so.

4 steaks of a large plaice weighing about 300g each or another firm-fleshed fish
Vegetable or corn oil for brushing
Sea salt and freshly ground black pepper
20-30 radishes, washed and discoloured leaves removed

For the Dukkah

50g shelled pistachio nuts
25g hazelnuts
25g flaked almonds
25g pinenuts
25g sesame seeds
tbsp fenugreek seeds
tbsp coriander seeds
A good pinch of saffron strands
12 black peppercorns, coarsely ground
25g sea salt flakes
tbsp caster sugar
1 tbsp thyme leaves

To make the Dukkah, lightly toast all of the nuts, then coarsely blend them in a food processor; add the other ingredients and give it all a quick blend again, making sure that the mixture has a nice coarse texture.

Preheat the barbecue, brush the fish with oil and season. Cook for about 7-8 minutes on each side depending on the thickness of the fish.

To serve, just scatter the Dukkah over the fish and serve with the radishes.

On Friday 10 July Mark Hix will be hosting an exclusive evening at the boutique hotel B+B Weymouth to launch the Dorset Seafood Festival in Weymouth. Independent readers have first crack at the tickets: prices are £300 per person in a standard double room, £310 per person in a seaview double room, or £310 per person of 2 couples sharing the apartment (all weekend prices inc. VAT). The package includes 2 nights' bed & breakfast at the B+B Weymouth, Fri 10 & Sat 11 July, champagne reception and canapés, 3-course dinner prepared by Mark Hix, and half a bottle of wine per person. Further information from bb-weymouth.com/cookwithmarkhix. How to book: telephone 01305 761190 or e-mail info@bb-weymouth.com. Please quote "Cook with Mark Hix!"