Cook bacon in a large skillet over medium heat, turning occasionally, until golden and crisp, 5 to 7 minutes. Transfer to a plate lined with paper towels, and drain. Stir together mayonnaise, grated garlic to taste, and a pinch of black pepper in a small bowl. Spread evenly on bread slices. Top 1 slice of bread with lettuce leaf, breaking to fit if necessary, and tomato slices. Sprinkle tomatoes with salt and pepper. Top with bacon and remaining bread slice. Slice sandwich in half before serving.