Method:

1. Measure flour and add it to mixing bowl..Add baking powder, salt and whisk it well.
   
2. Now measure sugar and butter and add it to mixing bowl.Whisk for atleast 3 mins.I used my electric beater , you can use hand whisk too.
   
3. Add egg and whisk for 2mins.Then add vanilla essence.
   
4. Scrap the sides, add flour and whisk again .
   
5. Once everything is combined, mix with a spatula,cling wrap and refrigerate atleast for 30mins.If your dough is stiff then you can start right away.
   
6. Meanwhile make a coarse sugar mixture.Transfer this to a plate,add cinnamon powder and mix well.
   
7. Preheat oven at 190 deg C for 10mins.Make small balls out of the dough(I used my measuring spoon to scoop out to get even sized cookies.Roll out in sugar-cinnamon mixture.Lay butter paper in baking tray, place the balls leaving atleast 1inch space.
   
8. Now using the bottom of a glass,gently press it to make the cookies slightly flattened.Bake in preheated oven at 190 deg C for 10-12mins or until the color changes to light golden.
   

Keeps well for about 2 weeks in room temperature itself!

My Notes:

• The cookies spread out so while baking so leave enough space between each cookie.
• I used 1 and 1/2 cups of flour, I used my 1/3 cup and added little more flour to make it 1/2 cup as I had butter in my 1/2 measuring cup
• My dough was slightly wet and moist so I refrigerated to make it stiff.But this step is optional, if the dough is stiff then start baking them right away.
• First I used 1 tbsp measuring spoon to scoop out the dough and the cookies are quite big so for the next batch(what you see in the pic)I took just half of 1 tbsp and the size was perfect.
• You can even refrigerate the dough overnight and bake the cookies next day.In that case keep the dough outside for a while then proceed.
• I added only 1/2 tsp of cinnamon powder as I wanted the flavour to be mild though the orginal recipe calls for 1 tsp of it.
• I followed the orginal recipe as such exact for few tweaks in the measure.So  am not sure of egg substitutes in this recipe.
• Do not be tempted to overbake just 10-12mins will be just fine.IT will be soft when taken out of the oven after cooling it is crisp at the edges and slightly soft inside thats how they are to be.