Sift three and half cups of the flour with baking powder, baking soda, cinnamon powder, ginger powder, cloves powder, nutmeg powder and salt.
Break eggs and separate the yolks and the whites. Soften butter by keeping it at room temperature. In a large bowl, cream butter and sugar until fluffy. Beat in egg yolks, one at a time, then the grated jaggery. Using a wooden spoon, stir in the flour mixture.
Cover and refrigerate the dough for at least one hour or overnight. Preheat the oven to 180°C. Grease three baking sheets. On a pastry board, sprinkle the remaining flour and roll out half the dough to one fourth inch thickness.
Cut out gingerbread people using cookie cutters. Transfer them back to the baking sheets with a spatula. In a separate bowl, whisk the egg whites with one tablespoon water.
Bake the cookies for five minutes, then brush lightly with egg whites. Bake two to three minutes more. Let them cool on the baking sheets for two minutes. Then transfer them onto racks to cool. Repeat with the remaining dough and flour.
Divide the royal icing into small cups and add different colours as you wish. When the cookies are cold, pipe out designs, such as smiling faces, zigzags, bow ties and aprons.
Let one color dry before piping the next.