Preparation Heat oil in heavy medium skillet over high heat. Add banana and sauté until golden, about 1 1/2 minutes. Using slotted spoon, transfer banana to paper towels to drain. Add onion to skillet; sauté 3 minutes. Add beans, cilantro, cumin, and cayenne; cook until mixture is hot, about 3 minutes. Using back of fork, mash bean filling to coarse paste; season with salt and cool. Preheat oven to 425°F. Roll out each puff pastry sheet on floured surfaceto 14-inch square. Cut each into 9 squares. Place 1 heaping tablespoon filling in center of 12 squares (reserve remaining squares for another use). Sprinkle each mound of filling with cheese, then top with bananas, dividing equally. Brush edges of squares with glaze. Fold 1 corner over filling to opposite corner, forming triangle. Using fork, seal crust edges. Arrange on rimmed baking sheet; brush with glaze. Bake empanadas until golden brown, about 15 minutes. Serve hot.
Preparation Heat oil in heavy medium skillet over high heat. Add banana and sauté until golden, about 1 1/2 minutes. Using slotted spoon, transfer banana to paper towels to drain. Add onion to skillet; sauté 3 minutes. Add beans, cilantro, cumin, and cayenne; cook until mixture is hot, about 3 minutes. Using back of fork, mash bean filling to coarse paste; season with salt and cool. Preheat oven to 425°F. Roll out each puff pastry sheet on floured surfaceto 14-inch square. Cut each into 9 squares. Place 1 heaping tablespoon filling in center of 12 squares (reserve remaining squares for another use). Sprinkle each mound of filling with cheese, then top with bananas, dividing equally. Brush edges of squares with glaze. Fold 1 corner over filling to opposite corner, forming triangle. Using fork, seal crust edges. Arrange on rimmed baking sheet; brush with glaze. Bake empanadas until golden brown, about 15 minutes. Serve hot.