01 -
Preheat oven to 350°F (conventional) and line a 9x13-inch tray with parchment paper. In a bowl, whisk egg yolks with 1/2 cup sugar, salt, and vanilla until light and fluffy, about 1–2 minutes. Whisk in milk, then sift in flour, cornstarch, and baking powder. Mix gently without overmixing. Separately, whisk egg whites with cream of tartar on medium speed until frothy. Gradually add 1/4 cup sugar, whisking until stiff peaks form. Fold a third of the meringue into the yolk mixture gently, followed by the remainder. Transfer batter to the prepared tray and bake for 15 minutes, or until done. Allow to cool completely.
02 -
Blend mango, yogurt, milk, sugar, and cardamom powder until smooth. Strain through a fine sieve to remove any pulp or fibers. Taste and adjust sweetness as needed.
03 -
Whisk together condensed milk, evaporated milk, milk, and half of the mango lassi. Adjust sweetness and consistency by adding more milk if the mixture is too thick.
04 -
Poke holes throughout the cake using a skewer while it remains in the tray. Pour a quarter of the mango lassi three milk mixture evenly over the cake and allow it to absorb fully, about 20 minutes. Repeat in 2–3 more additions, refrigerating between steps to ensure full absorption. If the mixture is too thick, dilute with extra milk as needed. Chill the cake in the refrigerator for several hours or overnight.
05 -
Whisk chilled heavy cream with the remaining mango lassi using a mixer with a balloon whisk attachment. Gradually add the mango lassi and whisk until firm peaks form. Taste and adjust for sweetness.
06 -
Spread a thick, even layer of mango lassi whipped cream over the soaked cake. Decorate with additional whipped cream (optional) and freshly chopped mango. Serve chilled.