Creating the Japanese Cotton Candy Swiss Cake Roll is straightforward when you follow these steps:

1. Preheat the Oven: Preheat your oven to 375°F (190°C). Grease and line a 15×10-inch jelly roll pan with parchment paper.
2. Prepare the Eggs: In a mixing bowl, beat the eggs and granulated sugar together until the mixture is thick and pale, about 5 minutes.
3. Combine Dry Ingredients: In another bowl, sift together the flour, baking powder, and salt.
4. Mix Wet Ingredients: In a small saucepan, combine the milk, vegetable oil, and vanilla extract. Heat gently until warm, but not boiling.
5. Combine Mixtures: Gently fold the dry ingredients into the egg mixture. Then, gradually add the warm milk mixture, folding until just combined.
6. Spread the Batter: Pour the batter into the prepared jelly roll pan, spreading it evenly.
7. Bake: Place in the preheated oven and bake for 12-15 minutes, or until the cake springs back when touched.
8. Cool the Cake: Once baked, remove the cake from the oven. Let it cool in the pan for 5 minutes, then invert it onto a clean kitchen towel dusted with powdered sugar.
9. Roll the Cake: Starting from one end, carefully roll the cake with the towel, creating a log shape. Allow it to cool completely in this shape.
10. Prepare the Filling: Once cool, unroll the cake gently. Spread the cotton candy evenly over the entire surface.
11. Roll Again: Carefully roll the cake back up without the towel. Place the seam side down on a serving platter.
12. Dust with Powdered Sugar: Lightly dust the finished cake roll with powdered sugar for an elegant touch.

These steps will guide you in creating this incredible cake roll effortlessly.