Toffee that is soft?

I have deep grooves in my back teeth, and regular toffee would get stuck in there easily, so I am looking to cook toffee that would turn out soft rather than hard.

Explanation; about ten years ago my mother cooked up such toffee by mistake. While I do not know for certain, I believe it was the following recipe the was botched:

• 1 cup sugar
• 1/2 cup butter
• 1/4 cup water
• 1/2 tsp. salt

Heat to boiling, until 285°F

My mother and I figured that perhaps everything was doubled except sugar (by mistake), so I attempted to recreate it like so. After letting it settle, the butter was starting to separate a little bit (it wasn't that bad). While the toffee was at room temperature or above, it was really hard and sticky, like caramel, and it was melting into the other pieces of toffee. After cooling it in the fridge it was surprisingly softer but not quite what I was hoping for. The texture of the original toffee from a decade ago was compared to peanut brittle by several people, however I don't remember it vividly enough to confirm.

I don't want to vainly waste ingredients so I'd appreciate any ideas on how to get my toffee as described.