In a large mixing bowl, add softened salted butter along with granulated and light brown sugars. Beat the mixture on medium speed for about 5 minutes, until light and fluffy.

Mix in the vanilla extract (or orange extract) until just incorporated.

Gradually add the all-purpose flour into the butter mixture on low speed, mixing until combined.

Fold in the dark chocolate chips and fresh orange zest.

Divide the dough in half and roll each half into a circular log, then wrap in plastic wrap and refrigerate for at least 2 hours.

Preheat your oven to 350°F (175°C). Prepare an egg wash by whisking an egg in a small bowl.

Brush the outer surface of the chilled logs with the egg wash, then roll in turbinado sugar.

Slice the dough into approximately ½-inch thick cookies and place them on lined baking sheets.

Bake the cookies for 12-14 minutes, or until the edges turn golden brown.

Let the cookies cool on the baking sheets for 10 minutes before transferring to a wire rack.