Break the roasted seviyan into several bits.
Heat a heavy-bottomed large saucepan on medium heat and add the tablespoon of butter and the seviyan. Stir for about 1 minute.
Pour it onto a plate and set aside.
Return the pan to the stove, and on medium heat, add the milk and bring it to a boil—about 10 minutes.
Once it boils, reduce the heat to medium-low.
Add the crushed cardamom and let it simmer uncovered for about 15 minutes until the milk is reduced slightly. Stir often, scraping the sides and bottom to avoid the milk sticking and burning.
Add the roasted vermicelli and let it cook for about 2 minutes.
Add the sugar and stir to dissolve. About 3 minutes.
Do a taste test and add more sugar if desired.
Add almonds, golden raisins, cardamom powder, and kewra drops.
Simmer for another 5 minutes,stirring gently, until the pudding mix is creamy.
Pour into a serving dish and garnish with reserved almonds and raisins.
You can serve Seviyan warm or chilled.