Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper or silicone baking mats. Do not grease the pans, as extra fat can cause the cookies to spread.

In a large mixing bowl, beat the softened unsalted butter and granulated sugar with a hand mixer or stand mixer fitted with the paddle attachment on medium speed for 3–4 minutes, until light, fluffy, and slightly paler. Scrape down the sides of the bowl once or twice while mixing.

Beat in the egg, vanilla extract, and optional almond extract on medium speed just until fully combined and smooth, about 30–45 seconds. If the mixture looks slightly curdled at first, continue mixing until it becomes smooth.

In a separate bowl, whisk together the all-purpose flour and fine sea salt. Add this dry mixture to the butter mixture in two additions, mixing on low speed after each just until no dry streaks remain. Avoid overmixing to keep the cookies tender and crisp.

Check the texture of the dough. It should be soft and thick, similar to very stiff frosting. If it is too firm to pipe, beat in 1 teaspoon of milk or cream at a time, up to about 2–3 teaspoons total, until it passes through your piping tip with steady pressure. If it becomes too soft, chill the bowl in the refrigerator for about 10 minutes.

Transfer the dough to a large piping bag fitted with an open star tip (such as Wilton 1M or Ateco 826). Add the dough in batches and press it down to eliminate air pockets. Twist the top of the bag to maintain consistent pressure while piping.

Pipe 2–2.5 inch circles, rosettes, rings, or 'C' shapes onto the prepared baking sheets, spacing them about 2 inches apart. For a traditional look, pipe small rings or crescents. If desired, sprinkle some cookies with coarse or sanding sugar for extra sparkle and crunch.

Place the baking sheets with the piped cookies in the refrigerator for 15–20 minutes. This brief chill helps the cookies keep their defined ridges and prevents excessive spreading during baking.

Bake one tray at a time for 10–14 minutes, rotating the pan halfway through baking. The edges should be just turning light golden brown while the centers remain pale. This color contrast is key for a crisp texture without overbrowning.

Allow the cookies to cool on the baking sheet for about 5 minutes, then transfer them carefully to a wire rack to cool completely. They will firm up as they cool, so don’t worry if they feel slightly soft at first.

Pipe and bake any remaining dough, chilling the trays between batches if your kitchen is warm. Once the cookies are completely cool, serve them with coffee, tea, or cocoa, or pack them into tins for gifting.