If there’s ever been a time to give in to cravings for retro comfort food, it’s now.

And that’s why I whipped up a tuna casserole. But not the classic, cream-of-something soup kind. I made a fancified version based on a recipe I fell in love with a few years ago when I wrote a profile of the London-based food writer Diana Henry.

Ms. Henry’s recipe is actually for a Breton tuna and white bean gratin adapted from her excellent cookbook, “Simple” (Mitchell Beazley, 2016). But with the elimination of several steps and the essential addition of a potato chip topping, I think it now falls squarely into tuna casserole territory. You can call it whatever you like.

To make enough for four, in an ovenproof skillet, sauté a chopped onion (or shallots, scallions or leeks) in olive oil over medium-high heat until soft, about 5 minutes. Add a pinch of red-pepper flakes, a pinch of salt and lots of sliced garlic cloves. Ms. Henry calls for six, and I happily complied. I also threw in a rosemary sprig, but it’s purely optional.

Adding a couple of anchovy fillets at this point would increase the umami, but I resisted because it felt too far outside the tuna casserole paradigm. I regretted it later.

When the garlic is slightly golden and very fragrant, add two (15-ounce) cans drained, rinsed white beans and about 1/2 cup of white wine. (I didn’t measure, but that’s what it felt like when I was splashing it in. You just want to moisten things up here.) And you don’t need to open a bottle of wine for this (I had an open one nearby). You can use 1/2 cup water or broth.

Let it simmer until the liquid evaporates and the beans are soft, about 5 minutes, then mash the beans with a potato masher or a fork. Make them as smooth or lumpy as you like. You just want to release some of their starch. Turn off the heat.

Now add 1/4 cup milk and 2 (5-ounce-ish) cans of tuna. If you have the oil-packed kind, add the oil. If you have the water-packed kind, drain them, and drizzle in more olive oil. Mash the tuna into the beans, leaving it a little chunky. Mix in a tablespoon or two of chopped fresh herbs (I used fennel fronds), grated zest from half a lemon and lots of black pepper. Finally, mix in 2 to 4 tablespoons grated any kind of cheese. (I used Gruyère, according to Ms. Henry’s recipe, but Cheddar or Parmesan or Jarlsberg would have been great, too.) Taste and add more salt and pepper if needed.

Spread the mixture evenly in the skillet, and top it with about a cup of potato chips that either you or your bored child crushed with a rolling pin. Scatter on more grated cheese, about another 2 tablespoons, and dot the top with, as Ms. Henry says, little nuggets of butter. She and I both agree that 1 tablespoon will do it.

Bake at 350 degrees, until the tuna mixture bubbles around the edges, 20 to 25 minutes. If you want the potato chips to get more brown, you could run the whole pan under the broiler.

Then dig in, squeezing some lemon juice over the top if you want to zip it up. My 11-year-old loved this, even after I admitted there was tuna in it, which she thinks she hates. Maybe it was the potato chips. Or maybe, tuna casserole was just what we all needed, whether we knew it or not.

This is part of a series in which Melissa Clark teaches you how to cook with pantry staples. See more.