Scrub apples thoroughly with warm water. Dry completely.

Line a half-sheet tray with greased parchment paper or a silicone mat.

Skewer each of the apples near the stem. Chill them in the refrigerator for a half hour or so.

Before making the caramel, ensure you have all ingredients out, measured and ready to go.

Make the caramel. Combine water, corn syrup and sugar in a saucepan and then cook over medium-low heat.

Once the sugar mixture turns a deep amber color and you begin to see wisps of smoke, take it off the heat.

Immediately pour in the heavy cream and butter, stirring vigorously until it all comes together. Be careful as it can bubble up and steam quite a bit. Mix in salt and vanilla.

Return the caramel to the stovetop and cook on medium-low until a candy or instant-read thermometer reads 245-249°F. (Alternatively, drop a spoonful of the hot caramel into cold water and form it into a ball. The ball should be firm but pliable.)

Pour caramel into a 2-cup liquid measuring cup, or a tall vessel wide enough to dunk the apples.

Let caramel cool to about 200°F. Dunk each apple about three-fourths of the way up, then scrape off the excess from the bottom. Place on the prepared sheet and repeat.

Let the caramel cool completely before drizzling in melted dark and white chocolate, or covering in M&Ms or crushed peanuts.