This Sicilian appetizer will keep in the refrigerator for one to two days. Bring to room temperature before serving.
To prepare caponata, heat oil in a large nonstick skillet over medium-high heat. Add eggplant, onion, bell peppers, and minced garlic, and saute 5 minutes. Stir in sugar, lemon juice, and salt; cook 1 minute. Stir in raisins, capers, and pine nuts. Place eggplant mixture in a large bowl; stir in basil.
Preheat oven to 375°.
To prepare crostini, place bread slices on a baking sheet. Bake at 375° for 7 minutes or until toasted. Rub cut sides of garlic clove over one side of each bread slice. Coat the bread slices with cooking spray, and bake an additional 2 minutes. Serve caponata with crostini.