Yam Layered Cake 芋头咖椰蛋糕

Ingredients 蛋糕材料:

4 egg yolks (粒蛋黄)
40g caster sugar  (幼糖)
80g corn oil  (粟米油)
80g milk  (鲜奶)
120g plain flour (面粉)
1/2 tsp baking powder （小匙发粉）

4 egg whites （粒蛋白）
1/8 tsp cream of tartar (小匙塔塔粉)
80g caster sugar (幼糖)

Filling 芋头咖椰材料:

300g yam (steamed until soft and mashed) 芋头（蒸熟压成泥）
500ml coconut milk (浓椰浆)
1 pack of hoen kwe flour (85g) (白色印尼綠豆粉(85g))
1/2 tsp salt (小匙盐)
180g caster sugar  (幼糖)
4 tsp agar - agar powder (小匙燕菜粉)
4 tsp instant jelly powder (小匙即溶遮哩粉)
400ml water (水)