Creepy Crawler Halloween Cupcakes

Ingredients

• 1 cup all-purpose flour
• 1/4 cup unsweetened cocoa powder
• 3/4 tsp. baking soda
• 1/4 tsp. salt
• 1/2 cup granulated sugar
• 1/2 cup firmly packed light brown sugar
• 4 tbs. (1/2 stick) unsalted butter, at room temperature
• 1 egg, at room temperature
• 1 tsp. vanilla extract
• 1/2 cup lukewarm water
• 1/4 cup buttermilk
• 1/2 cup heavy cream
• 1 tbs. light corn syrup
• pinch of salt
• 8 oz. milk chocolate, chopped
• 1 cup confectioners’ sugar, plus more as needed
• 2 tbs. milk, plus more as needed
• 1 tsp. vanilla extract