Way to grill: direct medium heat (350° to 450°F)
Grilling time: 13 to 17 minutes
1. Prepare the grill for direct cooking over medium heat. Brush the cooking grates clean. Grill the peppers over direct medium heat, with the lid closed as much as possible, until blackened and blistered all over, 12 to 15 minutes, turning every 3 to 5 minutes. Place the peppers in a bowl and cover with plastic wrap. Let stand for 10 to 15 minutes. Remove the peppers from the bowl and peel away and discard the charred skins. Cut off and discard the tops and seeds, and then finely chop the peppers. Transfer the chopped peppers to a medium bowl and toss with the bacon, 2 teaspoons of the oil, and the vinegar. Season to taste with salt.
2. Lightly brush or spray the cut sides of the bread with the remaining 4 teaspoons of oil and grill over direct medium heat until toasted, 1 to 2 minutes. Remove from the grill and cut the bread on the diagonal into 2-inch-wide pieces.
3. Just before serving, add the cheese to the bell pepper mixture. Spoon the mixture on the toasted pieces of bread. Sprinkle the basil on top and serve at room temperature.