I posted this in the thread I made for Aunt Bertha's birthday, but I figured I would add it here so more folks will see it!

Aunt Bertha’s Hot Fudge Sauce

Mix 4 oz. unsweetened chocolate
1 cup white sugar
1 cup dark Karo (dark corn syrup, Karo being a brand name)
1/4 cup water

Cook over moderate heat or in microwave, stirring constantly over heat, occasionally in microwave, until it forms a soft ball in cold water. Start checking after 4 minutes if you are using a microwave. Enjoy over ice cream.

It gets all stretchy and chewy when cold - if you put it in the fridge you can stand a spoon up in it, but just rewarm it, and spoon over cold ice cream, or whatever you need good dark chocolate sauce to complement, and there you are!

If you have a "candy thermometer" you can use it, otherwise the test is take a cup of cold water, and drip one drop in. If it just sinks to the bottom and flattens out, keep cooking. If it forms a soft round ball on the way down - it's perfect!