Prep the tomato topping. Stir together the diced tomatoes, basil, red onion, olive oil and a pinch of salt together in a mixing bowl until evenly combined. Cover and refrigerate for at least 15 minutes or up to 24 hours.
Add garlic. Slice off the ends of the garlic cloves (without removing the papery skins). Then rub the cut end of the garlic evenly over the tops of the bread slices to add as much or as little garlic flavor as you prefer, to taste.
Assemble. Taste the tomato topping and season with additional salt (and black pepper, if you'd like) to taste. Add a spoonful of the tomato topping mixture to each slice of bread, then drizzle a hint of olive oil over the tomato topping.
Serve. Serve immediately and enjoy!
Notes
Tomatoes: Always use the ripest fresh tomatoes that you can find. I typically use cluster tomatoes (a.k.a. tomatoes on the vine), Roma tomatoes or cherry tomatoes.