1 can + 1 cup canned milk
6 c white sugar
2 sticks margarine
5 T cocoa
1/2 bottle Karo syrup (1c+1T)
1 t vanilla

Cook to soft boil stage (112 degrees C). Add vanilla; beat until fudge begins to lose its gloss and is thickened. Pour in buttered pan or buttered table top. Cut when warm.

Source: Margaret Glass