butter for greasing pan(s)
2 1/2 cups honey roasted peanuts, divided
2 cups granulated sugar
3/4 cup water
1 cup light corn syrup or use brown sugar corn syrup
2 tablespoons unsalted butter
2 teaspoons vanilla
2 teaspoons baking soda

Generously butter two 15x10-inch jelly roll pans or one 17x12-inch jelly roll pan.
Grind 1/2 cup of the peanuts in a food processor until very fine; set aside.

Put the remaining peanuts in a bowl and set aside.

Put the butter and vanilla together in a small dish and set aside.

Put the baking soda in a small cup or dish and set aside.

In a heavy 3- to 4-quart saucepan over medium-high heat, bring the sugar and water to a boil, stirring with a wooden spoon. Add the corn syrup and cook without stirring to 280°. Add the 2 cups of honey roasted peanuts and continue cooking, stirring, to 300°. Remove from heat and quickly stir in the butter and vanilla. Stir in the baking soda. Immediately pour the mixture into the prepared pans. Spread with a heat resistant silicone spatula or use forks to pull the mixture to spread in the pan. Sprinkle with the reserved 1/2 cup of ground peanuts and pat with a spatula to help them stick to the brittle mixture. Let it cool and break up when thoroughly cooled.
Makes about 1 1/2 pounds.

Source: http://southernfood.about.com/od/candyrecipes