Char the peppers over a wood fire or under a broiler until blackened. When cool, peel (do not rinse), remove seeds, and slice into thick wedges. Arrange a platter with sardines, cherry tomatoes, onions, and goat cheese. Serve with a spoonful of skordalia and torn basil. Drizzle with olive oil.
For the skordalia: Combine all ingredients but salt and pepper in a bowl, mixing well. Season with salt and pepper to taste.