Combine all of the ingredients in a large bowl and toss to combine.
For the bruschetta:
Coat a stove-top grill pan or griddle with cooking spray and set over medium-high heat to preheat. Brush olive oil all over both sides of bread slices. Place bread on hot pan and cook 1 to 2 minutes per side, until golden brown. While still warm, rub garlic cloves all over bread. Serve bruschetta with ceviche.