Preheat the oven to 400°F. Line a rimmed baking sheet with parchment paper and set aside.
In a medium bowl, combine the tomatoes, garlic, 2 tablespoons of the oil, the lemon juice, basil, red pepper flakes, and salt, and season with pepper. Toss well and set aside.
Arrange the slices of bread on the prepared baking sheet. Drizzle the tops with the remaining 2 tablespoons oil.
Bake for 6 minutes, and then rotate the baking sheet 180 degrees. Bake until golden, 3 minutes. Let the toasts cool on the baking sheet for 2 minutes.
To serve, top the toasts with the tomato mixture, drizzle with the liquid from the bowl, and sprinkle with salt and pepper to taste.