Triple-stacked with bacon, lettuce, tomato, and grilled chicken. The club sandwich exists because sometimes you need a high protein lunch that's just really, really good.
Preheat a grill pan over medium-high heat. Brush chicken breasts lightly with olive oil and season both sides with salt and black pepper.
Grill chicken for 5-6 minutes per side, or until internal temperature reaches 165°F. Let rest for 3 minutes, then slice thin.
While chicken cooks, lay bacon slices in a cold nonstick skillet and cook over medium heat until crispy, turning occasionally. Drain on paper towels.
Toast all the bread slices in the toaster or on a dry pan until golden and crisp.
To assemble one sandwich: Spread 1 tsp mayonnaise on one slice of toast. Layer with lettuce, tomato slices, chicken slices, and a slice of cheddar.
Top with the second toast slice, add another thin layer of mayo, arrange bacon and remaining lettuce and tomato.
Close with the third piece of toast, press gently to compact, then cut sandwich diagonally into halves or quarters for serving.