Remove potato from oven, unwrap, and let cool. Scoop out insides of sweet potato and place in a food processor. Add garbanzos, olive oil, olives, garlic, and red pepper flakes. Purée until smooth. Add 1/3 cup basil leaves and pulse for 10 seconds. Season with salt and pepper, and transfer to a serving bowl. Garnish with sun-dried tomatoes and whole basil leaves.