Preheat your oven to 375°F (190°C). Line baking sheets with parchment paper.

Cream together softened butter, light brown sugar, and granulated sugar for a full 5 minutes.

Beat in eggs one at a time, then add vanilla extract, orange oil, and orange zest. Mix well.

In a separate bowl, whisk together all-purpose flour, baking soda, baking powder, and coarse salt.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Gently fold in the chopped milk chocolate bars until evenly distributed.

Using a #12 scoop, scoop out portions of dough onto prepared baking sheets, leaving enough space between cookies. Top with flakey sea salt and more chopped chocolate, if desired.

Bake for about 12-15 minutes or until the cookie has spread slightly and is golden brown.

As soon as the cookies come out of the oven, gently press a chocolate orange slice into the top of each cookie.

Allow the cookies to cool on the baking sheets for 25 minutes before transferring them to wire racks to cool completely.