1. Stir all ingredients except the baking soda together in a heavy sauce pan and bring to a boil.
2. Lower heat and simmer for 15 minutes stirring constantly or at least very regularly.
3. At the 15 minute mark or there abouts, add the big pinch of baking soda and continue to stir as it bubbles up.
4. Stir for another few minutes and take off the heat.
5. Pour into a well buttered pan; I used a glass Pyrex rectangular pan 6 1/2 by 10" but just try and find a pan a close size so that your toffee is not too thick. If all goes well, after it cools it should be just like a chewy toffee and can be sliced into squares or strips.