In a double boiler over hot water, place peanut butter to heat while preparing syrup.

In a large saucepan combine sugar, corn syrup and 1/4 cup of the water. Cook over high heat to 275 degrees on a candy thermometer. 

Reduce the heat to medium and add butter, stirring until melted.

Add peanuts and cook stirring for about 5 minutes or until candy starts turning brown and reaches 285 degrees on the thermometer. Do not overheat. It will make the candy hard.

Remove from heat, stir in baking soda that has been dissolved in a teaspoon of water.

Add vanilla and stir.

Working quickly, fold in the warmed peanut butter, while stirring gently.

Working quickly, pour candy mixture onto a well greased marble slab or a cookie sheet.

Spread as thinly as possible and cool quickly.

When cold …break into serving size pieces.