Step 1

Preheat oven to 375 degrees F. Coat a 10- x 15-inch rimmed baking sheet with cooking spray.

Step 2

In a medium bowl, combine flour, baking powder, and salt; mix well and set aside.

Step 3

In a large bowl, with an electric mixer on high speed, beat eggs 4 to 5 minutes, or until fluffy. Beat in granulated sugar, bananas, and 1 teaspoon vanilla. Fold flour mixture into banana mixture until well blended, then pour batter onto baking sheet.

Step 4

Bake 12 to 15 minutes, or until a wooden toothpick inserted in center comes out clean. Remove from oven and invert onto a clean kitchen towel that has been sprinkled with confectioner's sugar. While cake is still hot, roll it up jelly roll-style from the narrow end; cool on a wire rack. When cool, unroll cake and remove towel.

Step 5

In a small bowl, with an electric mixer on medium speed, beat 1 cup confectioner's sugar, cream cheese, butter, and remaining vanilla until creamy. Spread over top of cake, then roll it up again. Chill at least 2 hours. When ready to serve, drizzle with chocolate sauce and sprinkle with nuts, then cut into 1/2-inch slices.