Ingredients:

Butter 100g
Icing Sugar 1 cup
Eggs 3
All Purpose flour 1cup
Baking powder 1tsp
Vanilla essence 1/4tsp
Yellow food color (optional)

Method:

1-Beat butter+sugar till fluffy
2-add eggs one by one n keep beating
3-add remaining ingredients n mix well.
4-Grease butter paper in 7×7″ tray & Bake in preheated oven at 180 for 30mins.
5-cool it , cut into slices n bake for 20mins.
6-turn sides n bake for another 20mins
7-Let them cool completely.

Credit: Kitchenism