Orange Roll Cake

• 6-8 slices of orange
• Granulated sugar (2 tablespoons + 2 teaspoons or 38g)
• Water (approx. 3 tablespoons + 1 teaspoon or 55g)
• Eggs (about 5, each approximately 55g)
• Fresh orange juice (approx. 1/4 cup or 56g)
• Vegetable oil (3 tablespoons or 42g)
• Cake flour (1/2 cup or 66g)
• Granulated sugar (for the egg whites) (1/4 cup or 52g)
• Lemon juice (1 tablespoon)
• Vanilla extract (1 tablespoon)

Filling:

• Whipped cream (approx. 2/3 cup or 160g)
• Granulated sugar (2 tablespoons or 25g)
• Vanilla extract (1 tablespoon)
• Salt (1/4 teaspoon or 1.5g)

1. In a pot, combine fresh orange slices, sugar, and water. Heat until boiling, then cook on medium-low heat until little water remains. Transfer the orange slices onto parchment paper and pat dry with kitchen paper.
2. Line a baking tray with a silicone mat or parchment paper. Place the orange slices randomly.
3. In a clean bowl, thoroughly mix fresh orange juice, vegetable oil, cake flour, and egg yolks. Set aside.
4. Preheat the oven to 300°F (150°C).
5. To the egg whites, add lemon juice, sugar, and vanilla extract. Use an electric mixer until soft peaks form. Gently fold in the orange juice-flour mixture until just combined.
6. Gently pour the mixture into the baking tray.
7. Level it off. Tap to release air bubbles. Bake in the oven for 32 minutes.
8. In a clean bowl, combine whipped cream, sugar, salt, and vanilla extract, and beat with an electric mixer until it becomes thick and forms stiff peaks.
9. Remove the cake from the oven and let it cool on a rack before removing it from the tray. When the cake is cool to the touch, loosen the edges with a spatula, invert the entire tray onto parchment paper. Remove the tray and peel off the silicone mat.
10. Spread the whipped cream on the golden brown side, level it, and roll it up. Let the cake rest in the refrigerator for 15 minutes. Slice and serve.