Preheat the oven to 400F. Line a baking sheet with tin foil or parchment paper. Lay the bacon strips on the pan. Sprinkle half of the brown sugar and black pepper on the bacon. Use your hands to rub it evenly over each piece. Turn all the pieces over and repeat on the other side.
Transfer the bacon to the oven and bake for 10-20 minutes, until the bacon is your desired level of crispy.
While the bacon cooks, make the garlic basil mayo. Add all the ingredients (basil, mayo, lemon juice and zest, garlic, and salt) to a food processor or blender. Pulse until smooth. Set aside.
Cut the tomato into thick slices. Sprinkle with a pinch of salt and set aside.
Toast each piece of bread (optional).
To assemble, add a heaping tablespoon of the garlic basil mayo to each slice of bread. Add bacon, tomato, and lettuce. Sandwich together and enjoy!