Preheat oven to 350°F. Line muffin pan with baking cups.

In large bowl, combine cake mix, eggs, milk and oil. Beat with electric mixer on low speed 30 seconds, scraping bowl frequently. Beat on medium speed 2 minutes. Add chopped candy bars and beat until well combined. Fill baking cups 2/3 full with batter.

Bake 18-20 minutes or until toothpick inserted in center comes out clean. Cool cupcakes in pan on cooling grid 5 minutes. Remove from pan; cool completely.

For icing, melt caramels and water in small saucepan over low heat, stirring frequently, until smooth. Remove from heat.

In small saucepan, melt butter. Remove from heat and whisk in cocoa powder until smooth. Transfer to large bowl. With electric mixer, alternately add confectioners? sugar and milk until icing is smooth. If icing is dry, add additional milk, 1 tablespoon at a time. If caramel has thickened, warm slightly over low heat, stirring constantly, until it thins. Add warm caramel to icing and beat until combined.

Ice cupcakes; top with additional chopped candy bars.