Without a moment’s delay, I sprinkle the chocolate chips evenly over the hot toffee. I wait 2-3 minutes to let the heat from the pan soften the chips, then I use an offset spatula to gently spread them into a smooth, even layer of melted chocolate. This is the fun part! While the chocolate is still soft, I sprinkle on the chopped nuts and a generous pinch of flaky sea salt. Then, the hardest part: I let the entire pan cool completely at room temperature, then I transfer it to the refrigerator for at least 2 hours to set completely. The wait is agonizing, but it’s essential for that perfect, clean snap.
Pro Tips for Best Results
The type of baking sheet matters. A rimmed jelly roll pan (10×15 inches) is ideal because it contains the bubbling toffee perfectly. If you use a larger sheet, your toffee layer will be too thin; if you use a smaller one, it might overflow. I tested this three different ways, and the standard jelly roll pan gives you the perfect thickness.
For the cleanest break and easiest serving, score the chocolate lightly with a sharp knife after about 20 minutes in the fridge, once the chocolate has set but before the toffee layer becomes rock hard. You’re not cutting all the way through, just making guides. Then, when it’s fully chilled, you can break it along those lines for perfect pieces.
Don’t rush the cooling process. Letting it set at room temperature first prevents condensation from forming on the chocolate when you move it to the fridge. The full chill in the refrigerator is what gives you that signature hard, snappy texture. If you try to break it too soon, it will bend and be chewy instead of crisp.
Common Mistakes to Avoid
My first batch was a sticky mess because I didn’t boil the butter and sugar mixture long enough. I got nervous at the 2-minute mark and pulled it off. The result was a soft, gluey layer that never properly set. You must let it boil for a full, rolling 3 minutes to cook out enough water and reach the soft-crack stage. Set a timer and trust it.(See the next page below to continue…)