Step 1

Place the butter, sugar, corn syrup, heavy cream, salt and milk in a large, heavy-bottomed saucepan. Heat over medium heat until it comes to a boil.

Step 2

Meanwhile, whisk together the cocoa powder, water, rum and vanilla into a thin paste.

Step 3

Place the cocoa paste in a large bowl.

Step 4

Chop the chocolate into small pieces (or use excellent quality chocolate chips or paillettes) and add to the bowl.

Step 5

When the dairy comes to a boil, regulate the heat so it maintains a slow boil but doesn't boil up in the pan.

Step 6

Stir the dairy frequently and boil until it reaches a light caramel color, about 20-30 minutes (less time if you half the recipe). You don't want the color to be as dark as a Sugar Daddy, but it should be significantly darker than sweetened condensed milk. You can see what color it should be above in the post.

Step 7

Once the dairy is a lovely shade of deep tan, pour it into the bowl with the chopped chocolate and cocoa paste. Allow it to sit for a minute or two and then whisk until smooth.

Step 8

Strain it just to make sure it is completely smooth.

Step 9

Store in jars in the fridge.

Step 10

If you used fresh dairy, the hot fudge sauce will keep for a good 2-3 weeks in the refrigerator. If your dairy was close to the expiration date, use the sauce up within 5-7 days.