Preheat the oven to 180°C (350°F).

Grease a baking sheet with butter or ghee.

In a large bowl, combine all-purpose flour, sooji, gram flour, baking powder, and salt.

Add caster sugar, ghee, cardamom powder, and curd to the dry ingredients.

Mix until the ingredients come together to form a dough.

Wrap the dough in cling wrap and refrigerate for 3 hours (optional, but recommended for crunchier cookies).

Divide the dough into lemon-sized balls (about 25-30 balls).

Make a slight thumb impression in the center of each ball.

Dip the balls in crushed nuts (optional).

Arrange the Nankhatai on the prepared baking sheet.

Bake for 15-20 minutes, or until lightly golden brown.

Serve warm with tea or store in an airtight container.