Sieve together the flour, sugar, baking powder, and cardamom powder in a bowl.
Add the sesame seeds to the flour mixture.
Cut the butter into tiny pieces and rub it into the flour using fingertips.
Now slowly add the milk, one tablespoon at a time, to form a stiff dough. Make sure that the dough is not sticky.
Cover the dough and let it rest for about 30 minutes.
Grease the baking tray with butter. Preheat the oven to 350 F.
Divide the dough into 4 parts and roll each part into a ½ mm thick circle using little flour for dusting the surface.
Using a pizza cutter or the special sakarpara cutter, cut the rolled out dough into diamonds. The edges of the rolled out dough will be cracked. Cut those out and roll them back again and then cut out the diamonds.
Place the cutout shapes on the greased tray and bake for about 10 - 12 minutes. Keep an eye on the sakarpara for about 10 minutes as they tend to brown quickly.
Remove the tray from the oven and let it cool on the cooling rack.
Once completely cool, store the Sweet Diamond Biscuits in an airtight container.