Preheat oven to 350℉. Line two baking sheet with parchment paper and set aside.
In a large bowl, whisk flour, baking powder, and salt. Set aside.
Cream together butter and sugar until light and fluffy, about 3 minutes, in the bowl of a stand mixer fitted with the paddle attachment or in large bowl with a hand mixer.
Add the eggs and beat until light and creamy, about 2-3 more minutes.
Mix in vanilla extract, orange juice, brandy, and orange zest until well combined.
Add the flour mixture to the butter mixture, a cup at a time, mixing well after each addition. Beat on medium speed, about 1 minute, until a dough forms.
Break off a heaping tablespoon of dough (or weigh out the dough into 1.5 oz|43 g portions) and roll into a 7-8 inch rope. Fold in half and twist. Place the cookies on prepared baking sheets, about 2 inches apart.
Beat the egg yolk and milk in a small bowl and lightly brush on top of the cookies.
Bake 35-40 minutes, rotating the pans halfway, until golden brown.
Allow the cookies to cool for 5 minutes before transferring to a wire rack to cool completely.