First mix flax seeds powder in 1 & ½ tablespoon water, set aside.
Preheat oven at 190 deg C.
In a bowl, mix flour, salt and baking soda.
Take butter, sugar in another bowl and beat well until creamy for 2 mins using whisk or spoon.
Add vanilla, lemon juice, flax seeds mixture and mix well.
Top with the flour we mixed earlier.
Mix well to make a dough. It should be a single stiff mass. If too soft or gooey, refrigerate for 30 mins.
In a plate or bowl, mix sugar and cinnamon powder.
Scoop 1 tablespoon of cookie dough and roll over the sugar + cinnamon powder.
Line baking tray with butter paper/ baking sheet.
Arrange rolled cookie dough in it with enough space to spread.
Bake for 10- 12 minutes.
Take out and leave it to cool in the baking tray itself.
It will be soft when you take out from oven, but hardens as it cools.
Once cooled completely, you can store in an airtight container.