Preheat oven to 300°F. Line a baking sheet with parchment paper.

Sift together almond flour and powdered sugar into a bowl to remove any lumps.

In a separate bowl, beat egg whites and salt until foamy. Gradually add granulated sugar and continue beating until stiff, glossy peaks form.

Add the dry ingredients and orange zest to the meringue. Gently fold until the batter is smooth and flows slowly (thick, ribbon-like consistency).

Transfer batter to a piping bag and pipe small circles onto the prepared baking sheet. Tap the tray firmly to release air bubbles.

Let the macarons rest for 20–30 minutes, until a dry skin forms on top.

Bake for 14–16 minutes, until set. Let cool completely before removing from the pan.

To make the filling, beat butter until smooth. Add powdered sugar, orange juice, zest, and vanilla. Mix until light and creamy.

Pipe filling onto one shell and sandwich with another. Let sit for 30 minutes before serving for best texture. Enjoy!