Whisk together yogurt, rasmalai milk, oil and sugar, into a large bowl.
Sift the all-purpose flour, baking soda, baking powder, salt and cardamom powder into the same mixing bowl.
Fold in the dry ingredients into the wet ingredients till its evenly combined.
Line an 8 inch spring form pan with parchment paper or aluminum foil. Grease with butter.
Pour the batter into the prepared cake tin and tap against a counter to let it level out and to remove any air bubbles.
Bake in pre-heated oven at 350 F for 20 to 25 minutes or until a toothpick inserted comes out clean
Remove from oven and let the cake cool in the pan itself for 5 minutes
Remove the cake from the pan and move to a wire rack to let it cool to room temperature
After cooling, move back into the pan
Pour in the 1/2 cup of rasmalai milk over the cake. Spread it evenly with a pastry brush
Wrap the cake and pan with food grade plastic wrap