This recipe comes from the wife of one of my husband's co-workers. She made this peanut brittle and sent it to his office every year for Christmas. She also made a batch for my husband every year for his birthday (and he shared very little of it). When Mrs. Barney passed away, her husband started to make it for the office himself. When he retired he shared the recipe with us. I have always been afraid to try to make Peanut Brittle, but it was very easy. It makes an excellent brittle, crisp, airy and tender. I have made it with peanuts, cashews and pecans and they were all excellent
Butter a large sheet pan (10" X 15" or larger)and set aside on a heat proof surface.
Place sugar, water and corn syrup in large saucepan (mine is 4.2 qt size, which had room to spare). Bring to a boil over medium-to-medium high heat, stirring gently to dissolve sugar. Continue to boil to Soft Ball stage (240° on candy thermometer), stirring occasionally.
When syrup mixture has reached 240° add peanuts, vanilla and butter. Stir constantly, continuing to cook to Hard Crack stage (295°).
Remove from burner. Add baking soda. Stir ONLY until well mixed and foamy, but do NOT stir foam down.
Pour onto prepared sheet pan. DO NOT FLATTEN; allow it to settle on its own.
When brittle has hardened, but is still hot, sprinkle sugar on top.
As soon as brittle is hard and cool enough to handle, break up and place in an airtight container.
NOTES: Mrs. Barney stressed that the baking soda MUST be very fresh and should be purchased the day you are planning to make the brittle.
If using a candy thermometer, it is very important to attach the thermometer to the pan before heating the sugar/water/syrup mixture and allow the thermometer to heat with it. Be sure the bulb of the thermometer does not touch the bottom of the pan.
Clean up is very easy if you fill the pan with VERY hot water and let the pan and any utensils that you used sit in the hot water for a few minutes until the hardened candy dissolves.