Heat broiler to low with the rack 6 inches from the flame.
Brush the bread with 2 tablespoons of the oil. Toast under broiler until golden brown, 1 to 2 minutes. Set aside. Increase broiler to high.
Toss the tomatoes with the remaining oil, 1 teaspoon salt, and ½ teaspoon pepper. Broil on a rimmed baking sheet until charred and the juices are released, 8 to 10 minutes.
Meanwhile, divide the ricotta between the toasts. Top with the warm tomatoes and their juices. Season with freshly ground pepper and serve warm or at room temperature.