Wash and dry the apples thoroughly. Remove any wax if necessary by rubbing them with a cloth. Insert a wooden stick or popsicle stick into the top of each apple and set them aside.

Line a baking sheet with parchment paper. This will be the surface where the caramel-coated apples will cool.

In a medium saucepan over medium heat, combine the granulated sugar, unsalted butter, light corn syrup, and salt. Stir continuously until the butter melts and the mixture is smooth.

Attach a candy thermometer to the saucepan and continue to cook the mixture without stirring until it reaches a temperature of 240°F (115°C) to achieve the soft-ball stage.

Remove the saucepan from heat and stir in the vanilla extract. Allow the mixture to cool slightly for a few minutes until it thickens slightly.

Dip each apple into the caramel, swirling to coat the apple evenly. Allow any excess caramel to drip off before placing the apple on the prepared baking sheet.

If desired, sprinkle the coated apples with crushed nuts or sprinkles while the caramel is still warm. For a fancier touch, drizzle melted chocolate over the caramel once set.

Let the caramel apples cool completely at room temperature for about 30 minutes before serving. Optionally, refrigerate them to firm up the caramel further.