Carrot Cake Roll with Cream Cheese Frosting Filling

Preheat the oven to 375°F (190°C). Line a 15×10-inch jelly roll pan (or any similar-sized pan) with parchment paper. Lightly grease the parchment paper.
Sift dry ingredients: In a small bowl, whisk together the flour, baking powder, baking soda, cinnamon, nutmeg, and salt. Set aside.
Mix wet ingredients: In a large bowl, whisk the eggs and granulated sugar together until thick and pale (about 2-3 minutes). Add the vanilla extract and mix again.
Fold in the grated carrots: Gently fold the grated carrots into the egg mixture. Add the sifted dry ingredients and fold them into the wet ingredients. Be careful not to overmix.
Pour into pan: Spread the batter evenly into the prepared pan. Sprinkle nuts (if using) over the batter.
Bake: Bake for 12-15 minutes, or until the cake is lightly golden and a toothpick inserted in the center comes out clean.
Prepare for rolling: While the cake bakes, lay a clean kitchen towel on a flat surface. Once the cake is done, immediately invert it onto the towel. Remove the parchment paper, then roll the cake and towel together starting from one short end. Allow it to cool completely while rolled up.

In a medium bowl, beat the softened cream cheese and butter until smooth and creamy.
Add the powdered sugar, vanilla extract, and a pinch of salt. Beat until smooth and fluffy. Taste and adjust sweetness if needed.

Once the carrot cake is completely cooled, gently unroll it from the towel.
Spread the cream cheese filling evenly over the entire surface of the cake, leaving a small border at the edges.
Carefully roll the cake back up, starting at the short end, with the filling inside.

Place the rolled cake seam side down on a serving platter. Optionally, dust the top with powdered sugar for a beautiful finish.
Slice into rounds and serve chilled or at room temperature.