2 tablespoons capers, or to taste, rinsed to remove excess salt
Heat a cast iron grill over medium heat. Gently toss tomatoes with 1 tablespoon oil and cook on grill until wilted. Remove and cool.
Brush ciabatta slices with 1 tablespoon olive oil and rub with halved garlic. Place on grill pan and cook until lightly charred on each side.
Meanwhile tear basil leaves and place in a pestle and mortar and pound lightly. When broken down add vinegar and remaining tablespoon of oil. Mix well. Add black olives and pound to combine all ingredients. Finally add capers and pound a little, crushing some but leaving some whole. Taste and adjust seasoning if desired.
To serve, spoon caper, olive and basil mixture over toasted ciabatta.