Gregg’s Copycat Heath Bar Sheet Cake

by Victor Martelle

Yield: 9×13 inch Pan of Cake


  • 15 oz German chocolate cake mix
  • 14 oz sweetened condensed milk
  • 12 oz caramel sauce (see notes section)
  • 8 oz Cool Whip or thick whipping topping
  • 8 oz Heath bars
  • In cake mix directions, replace water with milk, oil with double amount of butter, add +1 egg,


  • 9×13 inch baking pan or similar
  • Cooking spray or oil
  • Large mixing bowl
  • Large spoon or paddle
  • Food processor or similar to chop/crush heath bars
  • Pan cover or aluminum foil

Let’s Make It!

  1. Defrost Cool Whip by placing in fridge.
  2. In large bowl, mix according to the directions but add the replacements noted above.
  3. Bake according to directions. Personally, I bake 1-3 minutes under recommended amount.
  4. Chop or crush the heath bars to use as spread later on.
  5. After cake finishes baking, take out of oven and let sit in pan for around 1 hour.
  6. Using the back end of a utensil, place holes 1-2 inches apart across the cake. Holes should reach at/near bottom.
Baked German chocolate cake in pan with holes scattered in it, caramel and sweetened condensed milk can next to it.
  1. Top cake with sweetened condensed milk and caramel. If you don’t want the bottom of this cake to become too moist or turn into a tres leches style cake, use about half of the required caramel and sweetened condensed milk.
  2. Place cake in refrigerator for 60 minutes to cool.
  3. Take cake out of fridge and using a paddle or spatula, gently spread the thawed Cool Whip over the cake.
  4. Cover the entire cake with crushed heath bar pieces. If using aluminum foil, try to cover the cake fully and evenly so Cool Whip doesn’t stick to the top of the foil. Feel free to use any leftover caramel and sweetened condensed milk to layer onto the toffee or use as a topping for later on.
  5. Cover cake and refrigerate for up to several days.

Notes & Alternatives

  • Use a caramel topping / sauce that is slightly thicker than regular syrup. Salted and non-salted work equally well.
  • This cake may taste better after 24 hours stored in the fridge because the ingredients get time to meld into the cake.
  • You may be able to replace the German chocolate cake mix with a chocolate variant.
  • Why replace the oil and water in the recipe with butter and milk? Many people find it tastes more full and rich. An extra egg also adds more density, flavor, and moisture as well. I’ve also heard of folks adding a packet of instant pudding, yogurt, and apple sauces.
  • You can make the cake from scratch yourself but I find using boxed cake and replacing the oil and water with butter and milk not only makes it taste as good as homemade cake, it’s a lot easier to make and lasts longer.
  • This cake is near identical in taste and texture to Gregg’s Heath Bar based toffee cake, at least, according to myself and everyone who has tried it!
  • Want to store it longer? This freezes really well.


  • Gregg’s was founded in 1972 in Warwick, Rhode Island, and has since become one of the most popular restaurants in RI known for their desserts.
  • They were once visited by former president Barack Obama where he ordered their Death by Chocolate Cake – he’s still alive after eating it!

Birds eye view of finished heath bar cake topped with caramel and sweetened condensed milk drizzle.
Side eye view of a finished Greggs Heath bar cake in a pan in the corner, heath bar candy and a slice of heath bar cake next to the pan.
Piece of heath bar cake on a fork with a blurred background of birds eye view of a finished Greggs Heath bar cake in a pan in the corner, heath bar candy and a slice of heath bar cake next to the pan.

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