Preheat oven to 350 degrees.
Spray a 9 x 13 inch pan with nonstick spray until coated.
Combine flour, baking powder, and salt in a large bowl - put to the side.
Separate eggs - yolks in one bowl and whites in another
Beat egg yolks with 3/4 cup sugar on high speed until yolks are pale yellow.
Mix in milk and vanilla.
Pour egg yolk mixture over the flour mixture and stir very gently with a spatula until combined.
Beat egg whites in a clean bowl on high speed until soft peaks form.
With the mixer still on, pour in remaining 1/4 cup sugar and beat until egg whites are stiff but not dry.
Fold egg white mixture into the batter very gently until just combined.
Pour into prepared pan and spread to even out the surface.
Bake for about 35 to 45 minutes or until a toothpick comes out clean.
Turn cake out onto a rimmed platter and allow to cool.
Combine condensed milk,coconut milk, and heavy cream in a small pitcher. With cake still warm, use a fork and poke holes all over the cake.
Slowly drizzle in the milk mixture - don't forget the edges.
Allow the cake to absorb the milk mixture for 30 minutes.
For icing - whip with very cold mixer beaters and bowl - 1 pint chilled heavy cream with sugar until thick and spreadable.