Grease a piece of baking paper and place it on a tray or baking sheet.

Insert bamboo skewers into all the apples and set aside.

Combine sugar, water, corn syrup, and black food coloring in a medium saucepan over medium heat.

Stir gently until the sugar dissolves completely.

Once dissolved, allow the mixture to simmer. Stop stirring and wash down the sides of the pan with a wet brush to prevent crystallization.

Cook until the candy reaches the hard crack stage (150ºC/310ºF). Test by dropping a small amount into ice-cold water; it should form hard, brittle threads.

Carefully dip each apple into the hot candy mixture, swirling to coat evenly.

Place coated apples on the prepared sheet and allow them to cool and harden completely before serving.