Add chocolate chips and coconut oil into the candy melting pot.
Turn the pot on high heat and mix regularly until all chocolate chips are melted and the melted chocolate reaches a smooth consistency.
If the chocolate is too thick, add more coconut oil, 1/2 tsp at a time.
Prepare a royal icing piping bag over a tall glass.
Split the melted chocolate into 2 piping bags.Cut 1 mm from the end of Bag 1, which will be used for edging.Cut 2-3 mm from the end of Bag 2, which will be used for filling.
Use Bag 1 to draw an outline around the cookie.
Use Bag 2 to fill in areas and spread the chocolate icing with the needle tool.
Tap the cookie gently on the table to level the chocolate icing and create a smooth surface.
Let the icing fully harden for 30-60 minutes before packaging.