Famous Fudge - cooking recipe

Ingredients

3 cups packed light brown sugar
1/3 cup corn syrup
1/3 cup whole milk (not lowfat or skim)
3 tablespoons butter
1 teaspoon pure vanilla extract
1/2 cup chopped walnuts (optional)

Preparation

Butter a 9-inch square pan and set aside.
In a heavy saucepan, combine sugar, corn syrup, milk and butter and then bring to a boil over medium heat, stirring constantly to dissolve sugar.
Insert a candy thermometer so that it doesn't touch the bottom of the pan and cook, without stirring, until temperature reaches 238F (115C) or soft-ball-stage, watching very carefully during the final minutes of cooking.
Remove from heat and stir in vanilla and the nuts, if using.
With a wooden spoon and a lot of elbow grease, beat fudge until it begins to thicken, about 7 to 10 minutes.
Pour into prepared pan and let cool; score with a sharp knife into squares or bars before the fudge is fully set.