Preheat oven to 350°F (180°C). Grease a 9×13-inch pan with butter; line with parchment if you like easy release.

In a large bowl, whisk warm milk, melted butter, sugar, cardamom, and saffron until the sugar mostly dissolves and the milk looks pale yellow.

Sift flour, baking powder, baking soda, and milk powder into the wet mixture.

Fold gently with a spatula until no dry streaks remain. Do not over-mix or the cake turns dense.

Pour batter into the pan and spread evenly. It will be a thin layer.

Bake 15 to 18 minutes until the top springs back when lightly pressed and a toothpick comes out clean.

Cool completely in the pan. Cut 12 rounds with a cookie cutter sized to your jars. Slice each round horizontally into two thin discs (24 total). Set aside.

Remove 8 to 9 rasmalai discs from their ras. Reserve about 1 cup ras for soaking and whipping.

Chop 6 discs into small pea-sized pieces for the middle layers.

Cut the remaining 3 discs into quarters (12 pieces) for topping one piece per jar.

Chill the mixing bowl and whisk attachment for 10 minutes if you can.

Beat cold heavy cream on medium-high until soft peaks form.

Add powdered sugar and 3 tbsp ras. Continue beating until stiff peaks form. Stop as soon as peaks stand up; overbeating turns cream to butter.

Place one thin cake round in the bottom of each jar. Press lightly so it sits flat.

Spoon about 2 tsp ras over the cake. It should dampen the sponge, not swim in liquid.

Pipe or spoon a layer of rasmalai whipped cream, about ½ inch thick.

Add chopped rasmalai pieces and a pinch of pistachios if you like nuts in the middle.

Add the second cake round. Spoon 2 more tsp ras on top.

Add another layer of whipped cream.

Place one quarter-piece of rasmalai on top for height.

Garnish with chopped pistachios, rose petals, a saffron thread, and a tiny flake of vark if using.

Cover loosely and refrigerate at least 2 hours, preferably overnight, before serving.