Cook the bacon. Cook 3 slices bacon, using one of these methods: stove, oven, or microwave. (If you’re making several BLTs, use the oven to cook the bacon, as it’s the easiest way to cook a lot of bacon). Make sure every slice is evenly crispy with no areas of unrendered fat. No flabbiness allowed! Transfer to a paper towel to drain.

Slice and season the tomato. Slice 1 small tomato crosswise with a serrated knife into ⅓-inch thick slices. Place the slices in a single layer on a double layer of paper towels (the towels will absorb some of the moisture, preventing a soggy sandwich). Season lightly with kosher salt and some black pepper. Let sit while you toast the bread.

Toast the bread. Toast 2 slices white sandwich bread until light golden brown.

Build the BLT. Spread 1 tablespoon mayonnaise on each slice of bread. Place 1 romaine lettuce leaf on one slice of bread, folding it as needed to fit neatly on the bread. Top with the seasoned tomato slices in a single layer (no need to pat the top dry), cutting them in half as needed to fit in a single layer. Tear the 3 bacon slices in half and place on top of the tomatoes in 2 layers. Close the sandwich with the second slice of bread mayonnaise-side down.

Cut the BLT in half. Gently press down on the top of the sandwich to compact slightly. Cut in half with the serrated knife and serve immediately.