Purple Yam Sponge Cheesecake
Recipe adapted from Happy Home Baking
(makes one 8″ cake)
125g cream cheese, cut into cubes
60g unsalted butter, cut into cubes
5 egg yolks (55g eggs)
1 teaspoon vanilla extract
1/4 tsp salt
75g cake flour
30g corn flour
1 tablespoon purple yam powder
1 tsp of blueberry paste for deeper color (optional)
5 egg whites
130g caster sugar
1/2 teaspoon lemon juice or cream of tartar
1. Line the base and sides of a 8″x3″ round cake pan with parchment paper.
2. Sieve together cake flour, corn flour and purple yam powder; set aside.
3. Melt cream cheese, salt and butter in a double boiler, stirring until mixture is lump free. Remove from heat and add the milk to temper.
4. Add the egg yolks and whisk to combine.
5. Add vanilla extract and whisk again.
6. Finally add the sifted flours, whisk the batter gently until fully incorporated. Set aside.
7. In a clean, dry mixing bowl, beat egg whites until frothy and foamy, add cream of tartar and continue to beat until foamy before gradually add sugar and beat to soft peaks.
8. Add the beaten egg whites to the cream cheese mixture in 3 separate additions until the batter is even and no streaks of white is visible.
9. Pour batter into the prepared cake pan. I pour it from a height slowly to help remove big air bubbles. Run a chopstick or skewer around the batter to remove big bubbles. Shake the pan lightly from side to side to level up the top.
10. Place cake pan in a baking tray filled with hot water and bake on lowest rack at 150C for 60-70 minutes. Remove the water pan, reduce the temperature to 100C and continue to bake for another 10 minutes.
11. Unmould the cake immediately and peel off the parchment paper on the side of the cake. Then invert the cake and peel of the base liner and reinvert back on to a rack to cool completely. Leave the cake to chill in the fridge for about 2 to 3 hours, best overnight, before serving.