Step 1

Cover the eggs with about an inch of water in a medium pot. Bring to a boil, remove from the heat, cover and let stand for 8 minutes. Drain and submerge in ice water. When cool enough to handle, peel the eggs and chop.

Step 2

Meanwhile, cook the bacon in a large nonstick skillet over medium heat until golden and crisp, about 4 minutes per side. Remove to a paper towel-lined plate. Crumble into bite-size pieces.

Step 3

Whisk together the mayonnaise, sour cream, lemon zest and juice, celery, reserved tuna oil, three-quarters of the scallions, 1/4 teaspoon salt and several grinds of pepper in a medium bowl. Add the tuna and three-quarters of the bacon and egg and gently fold together (do not overmix). Season with additional salt and pepper if needed.

Step 4

Sprinkle the tomato slices with salt and pepper.

Step 5

Double-up the lettuce leaves and fill each with some tuna salad. Tuck in a tomato slice. Sprinkle with reserved scallions, bacon and egg.