Recipe: Make-Ahead Bacon & Leek Casserole

updated May 1, 2019
Make-Ahead Bacon & Leek Casserole

A recipe for a cheesy bacon and leek egg casserole that can be prepared ahead of time and is perfect for Easter brunch.

Serves10 to 12

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(Image credit: Joe Lingeman)

I firmly believe that at the center of every Easter brunch spread there should be a savory, eggy casserole that’s served up in slabs and washed down with mimosas. Make this number your celebratory casserole this year. It’s filled with leeks, as an ode to the spring season, and is packed full of crowd-pleasing bacon and cheese.

Oh, and it can be made ahead of time, which really just seals the deal here.

A Spring Brunch Casserole That’s Filled with All Good Things

This simple casserole is a strata, which is basically a savory bread pudding, a sure bet for brunch. Leeks and bacon contribute to its salty, savory goodness, Dijon and thyme give it character, and shredded Fontina melts into nutty pockets that pull with every forkful. The whole thing can be prepared the night before so all you need to do is pop it in the oven in the morning. That’s fuss-free entertaining at its very best.

(Image credit: Joe Lingeman)

Make-Ahead Bacon & Leek Casserole

A recipe for a cheesy bacon and leek egg casserole that can be prepared ahead of time and is perfect for Easter brunch.

Serves 10 to 12

Nutritional Info


  • Cooking spray or oil

  • 1 pound

    day-old French or Italian bread, cut into 3/4-inch cubes (8 loosely packed cups)

  • 2 tablespoons

    olive oil

  • 6 large

    leeks, white and light green parts only, cleaned and thinly sliced into half moons

  • 1 teaspoon

    kosher salt, divided

  • 10 ounces

    bacon (about 10 slices), diced

  • 12 large


  • 3 cups

    whole milk

  • 2 teaspoons

    Dijon mustard

  • 1 tablespoon

    fresh thyme leaves

  • 1/2 teaspoon

    freshly ground black pepper

  • 3 cups

    grated fontina cheese (about 8 ounces)


  1. Coat a 9x13-inch baking dish (or another 3-quart baking dish) with oil or cooking spray. Place the cubed bread in the baking dish in an even layer; set aside.

  2. Heat the oil in a large skillet over medium heat until shimmering. Add the leeks and 1/2 teaspoon of the salt. Cook, stirring occasionally, until tender, 5 to 7 minutes. Transfer to a small bowl.

  3. Add the bacon to the skillet and sauté until the fat is almost all rendered out and it begins to get crisp, about 10 minutes. Using a slotted spoon, transfer to a paper towel-lined plate to drain.

  4. Whisk the eggs, milk, mustard, thyme, remaining 1/2 teaspoon salt, and pepper together in a large bowl.

  5. Spread the bacon over the bread cubes, followed by the leeks. Sprinkle the fontina on top, then pour the egg mixture over the entire thing. Press down on the top gently, so that all of the bread cubes get soaked a bit with the egg mixture. Cover and refrigerate overnight or if baking immediately, let the casserole rest on the counter while you preheat the oven.

  6. Arrange a rack in the middle of the oven and heat to 350°F. If you made the casserole ahead, take it out of the refrigerator so it can warm on the counter while the oven heats.

  7. Bake uncovered until the edges are bubbling and the top begins to brown, 50 to 65 minutes. The baking time will be greatly dependent on the depth of dish you use. Check the interior with a knife; if it comes out clean, the custard is baked through. (Cover with aluminum foil near the end of baking if the top is already browned.) Let cool for 5 minutes before serving.

Recipe Notes

Make ahead: The casserole can be assembled, covered tightly with aluminum foil, and refrigerated overnight before baking. Uncover and bring to room temperature before baking.

Storage: Leftovers can be stored in an airtight container in the refrigerator for up to 4 days.