Mix together the sugar and Karo syrup and microwave on high for 4 minutes

Mix in the peanuts in same bowl and microwave on high for an additional 4 minutes

Mix in the butter and vanilla and microwave on high for 30 seconds

Mix in 1 tsp of baking soda until mixture becomes foamy. Spread onto a lightly greased cookie sheet and let harden. Break into pieces and enjoy!