Combine sugar, corn starch, cocoa powder and salt in a small saucepan. Mix well. Whisk in milk. Cook over medium heat, stirring constantly, until mixture comes to a boil for 1 minute. Remove from heat and add chocolate chips, butter and vanilla extract. Let sit for 2 to 3 minutes and then stir until well mixed.
Let cool for 20 minutes. Portion into popsicle molds. Freeze for 2 to 3 hours or until solid. Unmold and enjoy!
Recipe Tip: Substitute small (2 to 3 ounce) paper cups for popsicle molds. Freeze 1 hour, then insert a wooden popsicle stick in the center of each.
Mint: add 1/2 teaspoon mint flavoring in place of vanilla
Peanut butter: Replace1-1/2 tablespoons milk chocolate chips with peanut butter chips
Spicy: Add 1/2 teaspoon cinnamon and 1/8 teaspoon cayenne
Mocha: Add 1 teaspoon instant coffee with the dry ingredients.