Prep apples: Wash and thoroughly dry apples. Remove stems and insert sticks.
Make caramel: In a saucepan over medium heat, combine cream, corn syrup, brown sugar, butter, and salt. Stir constantly until mixture reaches 240°F on a candy thermometer (soft-ball stage), about 10–15 minutes.
Add vanilla: Remove from heat, stir in vanilla.
Dip apples: Tilt pot and dip each apple, turning to coat. Let excess drip off.
Add toppings: Roll in toppings or drizzle extras before caramel sets.
Cool: Place on parchment-lined baking sheet and let cool completely.
Notes
Caramel can be made ahead and gently rewarmed.
A candy thermometer makes all the difference — aim for 240°F.