Crunchy chocolate biscuits filled with a smooth chocolate buttercream.
The unsandwiched cookies last for 4-5 days but the filled ones retain their crunchiness for about two days when stored in an airtight container. Make sure to store the cookies as soon as they are cool !
The biscuits will still be soft after baking. So handle only after they are cool and firm.
To get smooth edges , use the flat side of a spatula or a knife to press against the cookie edges once you place on the baking sheet.
Skip the salt in the biscuit recipe, if using salted butter.
The recipe can be doubled.
For crisper cookies, bake at 180 C for 12- 14 minutes.