My grandmother made this every Friday during Lent, and it melts in your mouth with only 3 ingredients

1 1/2 pounds thin flounder fillets (about 8 small fillets)

Preheat your oven to 375°F (190°C). Lightly butter a glass baking dish large enough to hold the rolled fillets in a single layer.

Pat the flounder fillets dry with paper towels so they’re easier to roll and will brown a bit on the edges. Lay them flat on a cutting board or clean work surface, prettier side down.

Divide the crabmeat into roughly 8 small mounds in the bowl so you have a sense of even portions. You want enough for a generous spoonful on each fillet.

Place a small mound of crabmeat near the wider end of each flounder fillet. Gently roll the fillet up around the crab, starting from the crab end and rolling toward the thin tail end, tucking the tail under if needed so it holds together.

Arrange the stuffed flounder rolls seam-side down in the prepared glass baking dish, nestling them close together so they stay snug while baking.

Slowly drizzle the melted butter over and around the fish rolls, making sure each one gets a good coating. Spoon a little extra butter over the tops so they glisten.

Cover the baking dish loosely with foil and bake for 12–15 minutes, until the fish is mostly opaque and just about cooked through.

Remove the foil and return the dish to the oven for another 5–8 minutes, or until the edges of the flounder are lightly golden and the butter is bubbling around the rolls. The fish should flake easily with a fork and the crab should be hot in the center.

Let the dish rest for 3–5 minutes out of the oven so the juices settle slightly. Spoon some of the melted butter from the bottom of the dish over each portion as you serve. Serve warm straight from the glass baking dish.

If you’re not strictly sticking to the 3-ingredient tradition, there are a few easy tweaks that still keep this weeknight-friendly. For a little brightness, squeeze fresh lemon over the fish right before serving or add a few lemon slices to the baking dish before it goes in the oven. You can also sprinkle a pinch of salt and black pepper over the fillets before rolling if your butter isn’t very salty. For more texture, top the rolls with a tablespoon or two of plain breadcrumbs mixed with a bit of melted butter for the last 5–8 minutes of baking. If flounder is hard to find where you live, thin fillets of sole or tilapia roll up nicely too—just aim for fillets that are flexible and not too thick. To meal prep, you can assemble the crab-stuffed rolls earlier in the day, cover the dish, and refrigerate; when you get home from work, just drizzle with melted butter and bake as directed, adding a couple of extra minutes if baking straight from the fridge.