This recipe make a very basic sponge toffee. I have had a very good response from the kids with this one.
As with any candy recipe, test that candy thermometer to make sure you know can hit the right candy temperature. A tip with this one, if it is not heated to 300 degrees or the hard crack stage, the toffee will be too soft and not as dark in color as it should be.
A springform pan should be pre-prepared by cutting out a circle for the bottom as well as lining the sides with parchment paper. The parchement paper must go past the sides of the pan - since the toffee will expand. I use a 12' pan and it still reaches the top, although it has not spilled over.
2 1/2 cups of white sugar
6 TBsp of water
2/3 cup of syrup
2 tsp vanilla
Bring the mixture to 300 degrees. Use the medium setting on your stove and give it time to reach 300. It takes about 20 minutes. The last few degrees go really fast and you have to keep close watch.
Remove from heat, quickly stir in 2 TBsp of baking soda and pour into your prepared pan.
At this point - leave it alone and try not to move it until it is cool. Then it can be broken up and stored in a sealed container. Do not leave it out in the air or it will soften. This is also very tasty dipped in milk chocolate.
I recommend you take a look at this Field Guide to Candy by Anita Chu. Invaluable if you like making candy!