• 1. Preheat the oven to 200 degrees F.
• 2. Line a baking sheet with parchment paper. 
• 3. Place egg whites and salt in the stand mixer and mix at medium speed until frothy.
• 4. Add cream of tartar and mix at medium high speed. 
• 5. Beat in sugar, 1 tbsp at a time. Tip: this step is very important, do not add all the sugar at one  time, add it in slowly. 
• 6. Add in vanilla extract and mix.
• The meringue will start to become stiff with peaks. To check if it is ready, roll a pinch of the meringue mixture between your thumb and finger and feel for any gritty sugar. If there is any present, continue to beat the meringue until it is gone and stiff peaks form.
• 7. Add several drops of green food coloring until you reach the desired tree-like color.
• 8. Prep a large piping bag by snipping the end and inserting a large star tip. Fold the pastry bag over and place inside of a glass or jar. Fill the bag with the green meringue.
• Tip: I like to use a 1M piping tip to get the best tree shape.
• 9. Squeeze out any air bubbles and twist the top of the bag.
• 10. Hold the pastry bag straight up and down on the pastry sheet and swirl it around from the center in a circular motion, gently pulling away when you have reached your desired height and size.  Create a Christmas tree shape by moving the piping bag, not the cookie tray.

Meringue tip:

• Meringues don't spread however, you don't want to place them too close as they need proper air flow during baking and dry time.
• 11. Bake for 1 hour and let stand as the oven cools to dry 2 hours or over night. Alternatively you can move the festive cookies to wire racks to cool.
• 12. For decorating melt the chocolate in a double boiler or microwave. Place it into a piping bag, cut the tip from the bag and draw chocolate stars on a parchment paper lined baking tray. Allow the stars to completely harden before attaching to the top of each tree with a dab of melted chocolate.
• 13. The final step is to dust with caster sugar if desired.