Place first four ingredients in a large nonstick frying pan. Set on medium heat. Do NOT change heat. When mixture starts to boil in the center let it continue boiling for 10 minutes, stirring at least every 30 seconds. Mixture will start to thicken. Stir in baking soda. Mixture will foam and turn white. Continue stirring about every 20 seconds for 1-2 minutes until brittle turns a nice golden color. Pour onto large cooke sheet greased with shortening. Qhickly spread as thin as possible using the back of a wooden spoon. Cool and break into pieces. Store in an airtight container. Enjoy!