How to BBQ prawns: tips from Mitch Tonks

Grilling prawns on the barbecue is one of the simplest, most rewarding things you can do with fresh seafood. The smell of wild-caught Atlantic King prawns on hot coals, everyone crowding round, nobody able to wait. It's the smell of summer. And because fresh prawns need very little done to them, getting it right is mostly about understanding heat, timing and knowing when to leave well alone.

Here, Rockfish founder Mitch Tonks walks through everything you need to know, from sourcing the best British prawns to the garlic butter finish that makes the whole thing sing.

Start with the best prawns you can get

Fresh prawns make an enormous difference on the barbecue. Mitch uses wild-caught Atlantic King prawns sourced directly from the boats at Brixham quayside in Devon, the same prawns served in Rockfish restaurants. They are meaty, sweet and hold up beautifully over direct heat.

You can order fresh wild-caught Atlantic King prawns from the Rockfish Online Seafood Market, packed at the quayside and delivered to your door the next day. This summer, spend over £75 and a free pack comes with your order.

How to prepare prawns for the BBQ

Keep it simple. Brush the shell-on prawns with a little olive oil and a good pinch of salt. That's your prep done. As Mitch puts it, you really don't need to do anything else. The oil helps the shells char evenly and the salt draws out that deep, briny prawn flavour. Anything more at this stage risks getting in the way.

Do not remove the shells before grilling. The shell protects the flesh from direct heat, keeps the moisture locked in and adds flavour as it chars. You want that smoky, golden shell.

Getting the BBQ temperature right for prawns

This is the most important step. You want your barbecue hot, but not absolutely baking. The coals should be glowing and white, not red and flaring. No flare ups. If flames hit the shells you get an acrid, bitter taste that overpowers the prawn and there's no recovering from it.

What you're after is steady, gentle heat. That's what gives you the lovely gentle smoke of grilling rather than the harsh taste of fire. Wait until the coals are settled and calm before you put anything on.

How long to cook prawns on the BBQ

Put the prawns shell-side down and leave them alone. Do not keep moving them or flipping them. The heat from the grill will work its way through. After 3 to 4 minutes you should see the shell start to lightly blister and a gorgeous golden colour developing. Use the edges of the grill to nudge any that aren't quite getting the heat to the middle. Then leave them again.

The moment the shell is blistered and golden, they are ready. Overcooked prawns turn rubbery quickly, so keep an eye on them in that final minute.

Using a lidded barbecue for prawns

If you are cooking on a barbecue with a lid, use it. Closing the lid turns the grill into more of an oven, wrapping all-round heat around the prawn and speeding up the cooking process. Close the vents too. Just a minute or two with the lid down and you get a gentle waft of smoke on the shells that is, as Mitch says, just so evocative of summer.

The Monolith Icon is Mitch's barbecue of choice for seafood. The ceramic construction holds heat beautifully and the lid gives you total control over temperature and smoke. It's available from Rockfish and participating retailers, and right now if you buy a Monolith BBQ you'll receive a free Rockfish seafood box worth £50. Find out more here.

The garlic butter finish

Once your prawns come off the grill, smooth garlic butter straight over the shells while they are still hot. The Rockfish garlic butter is the same recipe used in all of our restaurants, and it is the perfect finish for grilled prawns. Let it melt into the shells and get your fingers straight in. The oily, garlicky, salty sweetness all mixing together is the whole joy of it.

Serving grilled prawns

Serve straight from the grill onto a warm plate. A wedge of lemon on the side, good bread to mop up the garlic butter, and nothing else. Fresh British prawns cooked simply over coals do not need dressing up. If you want to build a bigger spread, grilled prawns sit perfectly alongside a Rockfish mixed grill of scallops, monkfish and squid, which is currently one of the most popular dishes across all of our restaurants.

Browse the full Rockfish BBQ seafood collection to build your own mixed grill at home.

BBQ prawn tips: a quick summary

• Use wild-caught, shell-on Atlantic King prawns for the best flavour and texture on the grill
• Season with olive oil and salt only. Keep prep simple
• Wait for coals to be white and settled with no flare ups before cooking
• Cook shell-side down and leave them alone for 3 to 5 minutes
• Use a lid if you have one for all-round heat and gentle smoke
• Finish with garlic butter straight over the hot shells
• Serve immediately with lemon

Frequently asked questions

How long do prawns take on the BBQ?

Shell-on prawns typically take 3 to 5 minutes on a hot barbecue. You are looking for the shell to blister and turn a deep golden colour. If you close the lid, the all-round heat speeds this up. Do not overcook them or the flesh turns rubbery.

Should you BBQ prawns with the shell on?

Yes. Cooking prawns shell-on on the barbecue protects the flesh from direct heat, keeps the moisture in and adds flavour. The shell chars slightly and gives you that wonderful smoky, sweet prawn taste.

What temperature should the BBQ be for prawns?

Hot, but not baking. You want glowing, steady coals with no flare ups. Flames hitting the shells give you an acrid, bitter taste. Wait until the coals are white and settled before you put the prawns on.

What is the best seasoning for BBQ prawns?

Olive oil and salt is all you need before the grill. A garlic butter finish while the prawns are still hot is hard to beat. The Rockfish garlic butter, the same recipe used in our restaurants, is perfect for this.

Where can I buy fresh prawns for the BBQ?

You can order wild-caught Atlantic King prawns from the Rockfish Online Seafood Market. They are sourced from the quayside at Brixham in Devon and delivered to your door the next day. Spend over £75 this summer and a free pack comes with your order.

Order fresh prawns from the quayside

Wild-caught Atlantic King prawns, sourced from the boats at Brixham and delivered to your door the next day. The same prawns Mitch grills in the Rockfish restaurants, now available to order direct from the coast.

Shop the Rockfish BBQ seafood collection at therockfish.co.uk