Preheat oven to 500°.
Pierce eggplant several times with a fork; place on a foil-lined baking sheet. Bake at 500° for 20 minutes or until tender. Cut eggplant in half lengthwise. Place in a colander; let stand 15 minutes. Peel eggplant. Cut into 1/2-inch cubes; place in a medium bowl.
Cut bell peppers in half lengthwise; discard seeds and membranes. Place halves, skin sides up, on foil-lined baking sheet; flatten with hand. Broil 15 minutes or until blackened. Place in a heavy-duty zip-top plastic bag; seal. Let stand 15 minutes. Peel; cut into 1/2-inch pieces. Add bell peppers and pine nuts to eggplant in bowl; toss well.
Heat oil in a nonstick skillet over medium-high heat. Add red pepper and garlic, and sauté 30 seconds. Add vinegar, capers, sugar, and salt. Bring to a boil; cook 30 seconds. Pour over eggplant mixture; toss. Marinate at room temperature for 2 hours.
Spoon 1 tablespoon eggplant mixture onto each bread slice. Serve immediately.