Have all ingredients at room temperature.

Preheat oven to 350°F and place oven rack in the center of the oven.

Spray a 9 by 13 inch pan with a non-stick vegetable spray then flour it.

In a large bowl whisk or sift together the sugar, flour, cocoa powder, baking powder, baking soda, and salt.

In another bowl, whisk together the eggs, water (and/or coffee), milk, oil, and vanilla extract.

Add the wet ingredients to the dry ingredients and stir or whisk until combined (the batter will be quite thin).

Pour the batter into the prepared pan and bake for 25 - 30 minutes or until the cake starts to pull away from the sides of the pan, it springs back when you lightly tap the middle of the cake, and a toothpick stuck in the middle comes out clean. Do not under-bake.

Poke holes in the cake with the handle of a wooden spoon or similar tool,(about an inch apart)

Pour on the sweetened condensed milk and use a spatula to evenly spread it over the cake.

Pour the slightly cooled caramel over the cake using the spatula to spread it.

Put the cake pan on a cooling rack and let sit until nearly room temperature, (45 mins)

Place cake in the refrigerator for at least 2 hours up to overnight.

Next, add the whipped cream to the refrigerated cake and spread evenly.

Top with chopped Heath toffee bars.

Serve right away or store in the refrigerator until used.

Mix the ingredients in a sauce pan, stir together and bring to a boil, (watch it carefully so it doesn't overflow).

Reduce the heat to low boil and cook for 6 1/2 minutes to thicken.

Remove from heat and let cool.

Use a hand mixer or stand mixer with a whisking attachment to beat the ingredients until soft peaks are formed, (4 to 6 minutes).