For the bruschetta, drizzle the bread with the olive oil and toast in a hot chargrill pan for 2-3 minutes on both sides, or until golden-brown and crisp.
For the topping, heat the olive oil in a frying pan and fry the onion and garlic for 2-3 minutes, or until softened, then add the tomatoes and season with salt and freshly ground black pepper. Cook for 3-4 minutes, or until the tomatoes start to break down slightly, then stir in the basil.
Serve the tomatoes on top of the bruschetta, and garnish with more basil leaves.