– Preheat the oven to 160°C. Line a 12” x 12” baking pan with parchment paper.
Mashed Purple Sweet Potato
- Skin the purple sweet potatoes and boil in water. Add pandan leaves knot and sugar.
- Boil until water is partially absorbed and purple sweet potatoes are soft.
- Mash purple sweet potatoes with remaining liquid. Let it cool down before use.
Purple Sweet Potato Topping & Filling
- Mashed purple sweet potato a couple of times through a fine mesh sieve.
- Whip the cream and fold in the mashed purple sweet potato.
- Topping – Fill 140g of mash into a piping bag with a No. 4 round piping tip. Set aside until ready to use.
- Filling – Set aside 280g of mash to spread on the cake.
Mix A
- Mix and sift Prima Top Flour Prima Superfine Wholegrain Flour and salt. Set aside.
- Melt cream cheese and parmesan cheese in milk together with sunflower oil. Set aside.
- Whisk egg yolk and sugar together until it turns pale yellow.
- Gradually add melted cheese mixture while alternating with flour mixture. Mix until well combined.
Mix B
- In a mixing bowl beat the egg whites on medium-high speed until foamy. Add in cream of tartar and increase the speed to high. Gradually add caster sugar and whisk until it reaches stiff peak and glossy.
- Add one-third of Mix A into the egg white mixture and fold gently to combine. Repeat with the remaining two-thirds of Mix A. Do not over-fold otherwise the batter will become lumpy.
- Pour batter onto the prepared baking pan and bake for 15 – 17 minutes.
- Once baked let it rest in the baking pan for 10 minutes. Remove cake from baking pan together with parchment paper.
- Slowly roll the cake away from you and wrap it using the parchment paper. Let it cool completely before creaming.
- Unroll the cake and spread the purple sweet potato filling. Roll up the cake and refrigerate for 1 hour.
- Remove from the fridge and pipe the purple sweet potato topping over the surface of the cake. Dust lightly with icing sugar.
- Serve chilled.