Put the 2lbs brown sugar in good size pan. Add 1 can Carnation or Pet Milk. Stir continuously on medium heat. Takes about 20 minutes
At soft ball stage, (myself I don't use a thermometer) I take a small amount from pan and put it into a cold bowl of water. If you can make the fudge into a ball, it's ready to come off stove.
Every few minutes take small amount from pan and put it into a cold bowl of water until it forms a ball.
Remove from heat. Add 1tsp. vanilla, and 1/4 cup of butter. Stir and then add about a jar and a half of peanut butter. Stir in until fudge starts to harden. Put in buttered cookie sheet or pan equivalent size. It makes about 3lbs of fudge. Sounds like a lot but it goes fast.
You can also add a few teaspoons of Marshmallow Creme and a bag of walnuts. Tasty, tasty, tasty