Marie Rose (seafood) sauce

This came to me in flash of inspiration one day (as it probably has to countless others).

I find that this conventional sauce swamps really tasty prawns, but it can be the saving of bland, frozen, pre-peeled ones (which may well be why it was invented, given the prevalence of the prawn cocktail in bad eateries).

With good prawns I’d rather have a decent home-made mayonnaise with low acidity and high garlic content - a gentle aïoli. If you’re not going in for langoustines, crevettes or tiger prawns, the best way to get tasty prawns is to buy them in their shells and dismantle them just before serving. (I find taking off the shells very tedious, because being a war baby, whose parents were allergic to any form of waste, I was brought up to pull the heads and tails off my prawns and eat the rest - shell, legs, eggs and all. Crunchy but much tastier.) An added advantage of buying and dismantling shell-on prawns is that the heads and shells form the basis of a fragrant fish stock, so bung them in a bag and keep them in the freezer until needed.

This sauce is good - better, actually - with other cold fish that has a stronger flavour than prawns, such as salmon or trout, and it’s excellent with Viv’s salmon mousse (previous recipe). I have deliberately avoided giving any quantities here so that you’re forced to mix the sauce to taste. Taste it with your prawns or other fish, though (keep some aside to allow for this pleasant quality-assurance activity).

Method Put some mayonnaise in a mixing bowl -– a bit less than the total amount of sauce you want. I use Sainsbury’s French Mayonnaise unless I’m just back from France, in which case either Mayonnaise au Citron (with lemon) or Mayonnaise de Dijon (with mustard) from the hypermarket make for interesting variations.

Shake in a dollop of tomato ketchup (I use Sainsbury’s Italian ketchup whether I’ve been to France lately or not) and stir thoroughly. Keep adding ketchup until the sauce is a convincing prawn-cocktail colour, then dip your finger in and taste. Add mayonnaise or ketchup until the balance seems right.

This works well just as it is, but lemon zest (see the comments in the salmon mousse recipe) and a drop or two of Worcestershire Sauce (careful - too much will wreck the colour as well as make the sauce tropically hot) both improve it.

If you don’t think it’s acid enough (this will depend as much on the mayonnaise as on the ketchup), put in some lemon juice. If you don’t think it’s sweet enough, put in some ordinary white sugar. (Don’t fall into the trap of thinking that acidity and sweetness cancel each other out. They don’t, but they do balance one another: you can stand a lot of acidity if there’s enough sweetness, and vice-versa, as in a good sweet wine.)

You can stir in some dried dill, and if you want to be really corny you can sprinkle the sauce with paprika when you’ve slopped it into the serving dish or over your seafood.

Finally, if you find the sauce a bit harsh, the best thing with which to dilute it is double cream (my favourite is Longley Farm from Holmfirth, where they film Last of the Summer Wine).

Since I wrote this, I’ve found Rick Stein’s recipe for what he calls ’Mary Rose Sauce’ (wasn’t a wrecked galleon of that name recovered off Cornwall or the Scillies some years ago?). It’s gratifyingly similar to my invention except that he cuts his mayonnaise 50/50 with Greek yoghurt. Try this as an alternative to my suggestion of using cream.