How to Fall in Love With British Fish Pie

It's a funny thing, food. It has so much potential to bring people together, but it can also create rifts of disagreement that simmer for years (okay, rifts don't simmer, but you know what we mean). A while back, we posted a basic recipe for pasta, minced beef, and tomato sauce that, in Emily's family, has gone by the name of "gamush" since time immemorial. We got two swift pieces of feedback from opposite ends of the family, each person claiming that they had invented it, and each explaining that we had gotten the recipe quite wrong (but in different ways). And that's just within one family!

Imagine how many opinions one has to contend with when it's a recipe familiar to whole nations, or even the world. It can be like taking a firm position on religion—no matter what you do, you're going to hear from plenty of people claiming that there's only One Correct Way, and it's not yours.

In Britain, fish pie is one of those dishes that can ignite such fierce debate. (Matt grew up there, so he knows fish pie passions firsthand.) The country is, relatively speaking, a small collection of islands, and the seafood of the North Sea is a cornerstone of its culinary heritage. Combine that with a climate befitting a nation at the same latitude as Greenland, and you've got a perfect environment for the cultivation of such dishes as cod and chips (don't call them fries!), parceled salmon, and the aforementioned fish pie.

Of course, everyone has their own notion of what makes the best fish pie. What kind of fish should be used? Should it have cheese? What about boiled eggs? Pastry or potato crust? You'll get as many different answers as there are fish in the sea. And there's an extra complication when you're adapting the dish to ingredients available in the United States, because, whether you're on the West Coast, the East Coast, or somewhere in between, the kinds of fish you'll have access to will be different.

You can go crazy with your fish combinations, but here are the general guidelines: For the backbone of the pie, you want a firm, white-fleshed fish that holds its shape during cooking, but will break into flaky pieces when cut with a fork. This is traditionally cod. Atlantic cod is available to the North Sea fishing industry that feeds the UK, but Pacific cod will be the variety available on the West Coast of the US. You can also use hake (this was our choice), halibut, or Alaskan pollack. It all depends on what's fresh, available, affordable, and sustainable, and your best friend in this decision will be your supplier—the seafood store or the fish counter at the grocery. You can also keep an eye on Seafood Watch to help you make sustainable choices. Right now, farmed Atlantic cod is a safe buy, but that doesn't mean you shouldn't cast a wider net to consider the alternatives.

Cod and similar fish are generally mild in flavor, so you need to combine that with other fish varieties that add a little richness and flavor. Often this role is filled by two different types: salmon, and a smoked fish such as haddock or mackerel. For simplicity's sake, we wanted to kill these two birds with one stone (or should that be "catch two fish with a single hook"?). That meant using hot-smoked salmon, which single-handedly delivers both some fatty richness and a deep, smoky flavor. Hot-smoked salmon, if you're not familiar with the term, isn't like the cold-smoked sliced lox that you would use to adorn a bagel. Our recipe provides instructions for hot-smoking your own, though you can also buy hot-smoked salmon to keep things simpler. Keep in mind that while it's faster and easier to buy it pre-smoked, you stand to save some money by smoking a fresh salmon fillet yourself.

If you do choose to follow our DIY path, the first step is to partially cure the salmon. Fully curing the fish, a process that enhances the flavor and aids in preservation, can take several days if you're thorough. For this recipe, we just want to prime the outside layers of the fish for the smoking process, and infuse it with a little flavor at the same time; longer-term storage is not our concern. To do it, we cure the fish for between four and 12 hours in a rub of salt, sugar, mustard powder, and lemon zest. You'll notice that the process dramatically changes the color of the salmon, from its initial pink to a deeper red, even after just a few hours.

Once you're ready to smoke it, wipe most of the rub off the fish, but don't rinse it. You can use a smoker if you have one, but this process works just as well on a charcoal grill. All you need is a foil pan of water and soaked wood chips. Most types of wood work fine, but we avoid mesquite, which tends to overpower all the delicate flavors in the pie.

Cooking with smoke is a slower process than straight grilling, but we still want the inside of the fish to cook through to about medium, just enough to allow it to flake easily while still keeping it tender and juicy. We do that by cooking it to medium-rare—125°F (52°C) in the thickest part of the fillet—then wrapping it in foil and letting it stand for about 20 minutes. The residual heat will provide just enough carryover cooking to bring it up to medium. Once that's done, you can flake it into nice big chunks.

For a little extra texture, we like to mix some shrimp into the pie as well. Because shrimp cook quickly, you don't want to use small ones that will overcook and turn rubbery. Instead, opt for medium or large shrimp. If you find extra-large or jumbo, these will work well cut into slightly-larger-than-bite-size pieces. We take one extra step with the shrimp after cleaning them and before cutting them up: We briefly soak them in a brine of salt and baking soda. This takes only 15 minutes, but it does wonders to keep the shrimp moist and firm during cooking.

The filling of the pie is essentially a leek, parsley, and cream sauce that adds an oniony richness, but is mild enough to let the fish shine through. You could use actual onions, but we prefer leeks, as they deliver a milder oniony flavor that works better with the seafood.

As for the pie crust, you could definitely go with a puff pastry version, and we've had some great pastry-topped fish pies in our day, but for this recipe, we're going with simple mashed potatoes. We want the crust to remain stable, so we use this recipe for fluffy mash, but hold back a little on the liquid. To get that essential brown, crunchy top, we use a few dabs of butter and some sprinkled panko. You could also add a little scattered Parmesan or Romano cheese.

We're not saying this is the definitive fish pie—lord knows there are too many opinions out there to safely claim that title. So let's think of this as a conversation starter, one we can all thoroughly enjoy no matter whether we think it's "correct" or not.