Wash and dry the apples thoroughly. Firmly insert wooden sticks into the tops and line a tray with parchment paper, lightly greased.

In a medium saucepan, combine sugar, corn syrup, and water. Heat over medium-high, swirling occasionally. Cook until it reaches 300°F (hard crack stage), then remove from heat and stir in vanilla extract.

Divide the hot syrup into 3–4 small bowls and tint each with gel food coloring. Quickly drizzle the colored syrup back into one bowl in thin streaks, leaving them un-stirred for a marbled effect.

Holding the stick, slowly dip each apple into the candy mixture, twisting to ensure an even coat. Let any excess drip off before placing the coated apples on the greased parchment. Dust with edible glitter while still warm.

Allow the Galaxy Candy Apples to cool and harden completely at room temperature, which will take about 30 minutes.