Prep Your Workspace: Line two baking sheets with parchment paper and preheat your oven to 300°F (150°C).

Make the Macaron Shells: Sift almond flour and powdered sugar in a large bowl. In another bowl, whip egg whites with granulated sugar until stiff peaks form. Fold the dry mixture into the meringue.

Pipe the Shells: Transfer batter into a piping bag and pipe even circles on prepared sheets. Tap to release air bubbles.

Rest the Macarons: Let piped macarons rest for 30-60 minutes until a skin forms.

Bake the Shells: Bake the macarons for 15-20 minutes until they rise and develop feet.

Cool the Shells: Remove from the oven and let cool on sheets for 10 minutes before transferring to a wire rack.

Make the Butterscotch Filling: Melt butterscotch chips and heavy cream over low heat, stir in butterscotch flavoring and let cool.

Assemble the Macarons: Pipe filling onto half the shells and sandwich with the other halves.