Masterclass
Choosing prawns
Prawn cocktails live and die on the quality of the prawns. Luckily, Australian prawns tend to be fantastic across the board.
Start by choosing the size you want. The grading system for HOSO (head on, shell on) whole prawns ranges from jumbo U6 prawns at one end of the spectrum, to small U30/40 prawns at the other. The numbers refer to the minimum number of prawns per pound, so U6 will have fewer than six prawns per pound (roughly 13 per kilogram), and U30/40 (usually called school prawns), have about 30-40 per pound or 66 to 88 per kilogram.
For a prawn cocktail, I think U10 shellfish are perfect. They’re sold in Australia as “large” prawns, and you’ll normally get about 22 per kilo. But if you like larger prawns, go for U8 (“extra large”).
To check for freshness, look at the head. Prawns have a reputation for going off quickly because bacteria in the head can multiply quickly. This turns the head of the prawn black, something that can happen within hours. The discolouration isn’t hugely dangerous, but it can indicate that the prawn either isn’t fresh or has not been handled properly. Avoid buying prawns with black heads, if you can.
Poaching from scratch
I learned this cooking method from Anthony Huckstep, who, along with John Susman, Steve Hodges and Sarah Swan, literally wrote the book on the subject – Australian Fish and Seafood Cookbook: The Ultimate Kitchen Companion.
The key is to use quite a lot of salt and vigorously boiling water. It may seem like an absurd amount of salt but boiling prawns with the shell on means most of that salt will not end up seasoning the prawn flesh.
Once cooked, cool them quickly so they remain nice and juicy by scooping them from the pot into a large bowl filled with ice and just enough water to cover.
Frozen pre-cooked prawns
Starting with raw prawns and boiling them yourself will make a big difference to the quality of your prawn cocktail. But realistically, many of us will opt for pre-cooked prawns, especially around Christmas.
Prawns are usually cooked, chilled and frozen soon after being caught, often on the boat before it even returns to shore. We have excellent prawn fishers in Australia who treat their catch well, so pre-cooked prawns are a safe, delicious, and easy choice.
Because they are usually frozen before being distributed, it makes little difference to the quality whether you buy them during the Christmas Eve rush or months beforehand. If you have the freezer space, you can buy them now.
One small gripe: pre-cooked prawns are usually not boiled with enough salt for my taste, and are often cooked a little too long to ensure they are safe in transit. There’s little you can do about the second part, but for the first part, make sure you season them well after you’ve peeled them.
To defrost pre-cooked prawns, the fridge is best. They will take 8-12 hours to fully defrost so remove the prawns from the freezer and leave them in the fridge for about that long, then rinse them in heavily salted cold water before returning them to the fridge. This will reduce any bacteria that might still be around the prawns and help them keep for longer.
Lettuce prep
The lettuce in a classic prawn cocktail is there for textural contrast, so choose a crunchy iceberg or cos. There’s no need to be fancier than that. The inner leaves of both iceberg and cos will have more crunch than the dark green outer leaves.
I like to wash the lettuce thoroughly, pick off any discoloured parts, and chill the leaves well in plenty of cold water. This will ensure it doesn’t wilt. You can even keep the leaves in a bowl of water in the fridge for days. Just before serving, spin the leaves dry and chop them so they keep their crunch.
Choose the right mayo
I use Japanese mayonnaise for my Marie Rose sauce because it has a creamier texture than most store-bought mayonnaises, which are often sharp and sour, and have a gelatinous texture from being thickened with gums.
They can be fine in a sandwich but they’re too tangy and gloopy in a Marie Rose sauce, which is thinned and sharpened with lemon juice. Some recipes try to combat this by incorporating sour cream or creme fraiche, but I find that simply using Japanese mayonnaise gives my Marie Rose sauce the perfect texture.
