This recipe has all of the flavors of your favorite BLT sandwich but in a comforting, easy-to-make tomato soup. The rendered bacon fat is used to flavor both the base of the soup and the crispy croutons that you sprinkle on at the end. For a final flourish, we finish the soup with a rustic green sauce called pistou. If you don’t have the time (or energy) to make your own, feel free to swirl in your favorite store-bought pesto instead.
MAKE AHEAD The pistou can be covered and refrigerated overnight. Bring to room temperature before serving.