Drizzle each slice of bread with 1 tablespoon of olive oil. Toast the bread until golden brown in a hot pan.
Rinse and quarter the tomatoes. Remove the seeds and finely dice. Mix the tomatoes with the shallot, lemon juice, remaining oil, and basil. Season to taste with salt and pepper. Set aside and marinate for 5 minutes.
Top the bread slices with the tomato mixture and serve immediately.