Immediately add peanuts and stir constantly until thermometer reaches 300°F (hard crack stage). Remove from heat and quickly add baking soda and vanilla, mixing well. Spread immediately on 2 warm well buttered cookie sheets. When cool, lift from pan using knife and spatula and break into bite size pieces.

Note About Candy Thermometer: Place clamp on side of pan and lower temperature at least 2-inches into liquid, keep stem of thermometer off bottom and sides of pan.

Temperature will reach 212°F, remain for about 10 minutes and then slowly rise to desired temperature which can take 45 minutes.