Dissolve 1 tablespoon of instant coffee in 2 tablespoons of hot water and let it cool.

In a mixing bowl, beat 1 stick of room temperature unsalted butter with 1 cup of icing sugar until fluffy.

Add 1 large beaten egg and mix until fully combined.

In a separate bowl, whisk together 2 cups of all-purpose flour, 1 tablespoon of cornstarch, and 1 teaspoon of ground cinnamon.

Fold cooled coffee mixture into butter mixture, then gradually add dry ingredients until just combined.

Pipe the dough into desired shapes on a lined baking tray.

Chill the baking tray in the freezer for 5-10 minutes.

Preheat oven to 350°F (175°C) and bake for approximately 8 minutes.

Allow cookies to cool, then dip edges in melted dark chocolate and sprinkle with chopped pistachios.