In a mixing bowl, cream together the unsalted butter, sugar, and light brown sugar until the mixture is smooth and fluffy.

Add in the egg yolk, salt, vanilla extract, and almond extract (if using). Mix well until thoroughly combined and creamy.

Gradually add the all-purpose flour to the mixture. Stir until just combined.

Divide the dough into two equal portions. Roll each portion into a log, about 2 inches in diameter.

Wrap each log tightly in plastic wrap and chill for at least 1 hour.

Preheat your oven to 350°F (175°C).

Remove the chilled logs from the refrigerator and slice them into 1/4 inch thick rounds.

Place the cookie slices on a baking sheet lined with parchment paper.

Before baking, sprinkle colorful Nonpareils over the tops of the cookie slices for that festive touch!

Bake in the preheated oven for 10-12 minutes, or until lightly golden around the edges.

Allow the cookies to cool on a wire rack before serving.