This recipe requires a bit more concentration than the last, but it's my favorite. My mother makes it every Christmas, and no one makes fudge as well as my mother. Fortunately, I've found that while I don't make fudge as well as her, as long as I don't burn this recipe it's really good!!(Even the time that we had to eat it from bowls with spoons because I was too impatient to wait for it to finish cooking...) I don't have a candy thermometer, but the 'soft ball stage' is the same as 235 degrees.
3c brown sugar
1 tin sweetened condensed milk
Pour sugar and milk into a med-sized pan. Stir over low heat for 20mins. Turn up heat and cook until it reaches the soft ball stage. Remove from heat and add butter. When it has cooled add vanilla and beat well.