Melt butter in a saucepan, remove from heat and add in the chocolate. Mix well until the chocolate melts and the mixture gets smooth. If somehow the chocolate doesn't easily melt, put the saucepan back on the lowest heat. Melt the chocolate stirring constantly. Or use a double broiler to melt butter and chocolate.

In a large bowl, whisk together eggs, sugar, vanilla extract and salt until pale yellow.

Pour the chocolate mixture into egg mixture gradually and mix well.

Add in flour, baking powder and 1 teaspoon orange zest. Stir until incorporated. Cover the dough and chill for 30 minutes.

Preheat oven to 350F (180C).

Line two baking sheets with parchment paper. Scoop cookies on it, leaving 2 inches between each cookie. Grate half of the remaining orange zest over them. Bake for 8-10 minutes. Don’t over bake! We bake them for 8 minutes but every oven is different. Test with one cookie if you want.

Use a spatula and transfer the cookies on a cooling wire rack right after you remove them from oven. Sprinkle extra orange zest and sea salt over each cookie when they are still warm, gently pressing over them.