Preheat your oven to 325°F (165°C). If using dried coconut flakes, rehydrate by soaking them in warm water for 5 minutes, then drain and squeeze out any excess water. If using fresh coconut, proceed directly with the recipe.

Skin the pistachios for a brighter green color (optional but recommended). To do this, process the pistachios in a food processor until they resemble fine crumbs (be careful not to make a paste).

In a small bowl, beat the egg and egg white together. Stir in the pistachio crumbs, shredded coconut, sugar, cornstarch, rosewater (or vanilla extract), and a pinch of salt. Mix everything well with a fork, ensuring the ingredients are evenly combined.

Line a baking sheet with parchment paper or a silpat mat. Scoop rounded tablespoonfuls of the coconut mixture and shape them into haystack-like mounds on the baking sheet. Space them evenly apart.

Bake the macaroons for 25-30 minutes, or until the bases turn light golden brown. Do not overbake to avoid dryness. Once done, remove from the oven and allow them to cool completely on the baking sheet. They will firm up as they cool.

While the macaroons cool, melt the dark chocolate in a microwave-safe bowl or double boiler. If using the microwave, heat the chocolate at 50% power for 1 minute, stir, then continue to melt in 15-second bursts at 50% power until smooth.

Once melted, dip the top of each macaroon into the chocolate, twisting it to coat about 1/4 inch up the sides. Place the dipped macaroons back onto the baking sheet.

Allow the chocolate to set before serving.