Begin by separating the coconut cream from the liquid in the refrigerated coconut milk cans. Whip the cream with powdered sugar and vanilla extract until smooth and fluffy. Add cornstarch if needed for thickness, then fold in the coconut flakes.

Prepare the pandan chiffon cake by first beating egg whites with cream of tartar to stiff peaks, gradually incorporating 100g of the sugar until glossy. Set aside.

In a separate bowl, mix egg yolks, milk, oil, vanilla extract, and pandan extract. Add flour, remaining sugar, and baking powder, blending into a smooth batter.

Gently fold the whipped egg whites into the pandan batter, taking care to retain the airy texture.

Pour batter into a chiffon pan, tapping to release air bubbles, and bake at 350°F (175°C) for 30-35 minutes, or until springy to the touch.

Allow cake to cool upside down in the pan before removing and spreading generously with the coconut cream frosting.