Preheat oven to 350 degrees F.

In large bowl, cream together butter and 1/2 cup sugar. Beat in corn syrup, egg, and vanilla. In medium bowl whisk together flour, cocoa powder, salt, and baking soda. Gradually mix dry mixture into butter mixture. Cover and refrigerate dough for 1 hour.

Place remaining 1/4 cup sugar in small bowl. Scoop and roll dough into 1-inch balls. Swirl the balls in the bowl of sugar until coated. Place 2 inches apart on ungreased baking sheet (approx. 12” x 17”.)

Bake for about 9 minutes or until set and just starting to crack. Remove and allow to cool for 1 minute. Use a rounded 1 teaspoon measuring spoon, melon baller or your thumb to press an indentation into the cookie. It should go at least halfway down through the cookie. Remove to cooling rack. Repeat to use up all dough.

Add white chocolate to medium heat-proof mixing bowl. Bring cream to boil in saucepan. Pour hot cream over chocolate and whisk until smooth and combined. Stir in peppermint extract.

Use teaspoon or piping bag to fill each cookie with peppermint ganache. Sprinkle each with a pinch of crushed peppermint candies.