Preheat oven to 350 degrees.
In a medium mixing bowl mix together flour, baking powder and salt.
In a stand mixer or large mixing bowl with an electric mixer, beat butter until light in color and airy. Add in sugar mix until smooth. Next add in egg, orange zest, orange liqueur or orange juice, and mix until fluffy and combined.
Add in dry ingredients slowly and mix until just combined. Do not over mix.
Stri in dark chocolate until combined.
Using a cookie or 2 tbsp measure scoop, place cookie dough onto parchment paper on a cookie sheet. Bake for 12 to 15 minutes or until edges are just lightly golden.
Cool on a cooling rack.
In a small bowl mix powdered sugar, orange liqueur or orange juice, butter, and orange zest until smooth. Dip tops of cookies into glaze and let dry on cooling rack.
Garnish with chocolate shavings, more orange zest, and flaky sea salt while the glaze is still wet for a beautiful cookie.