Preheat oven to 350° F. Spread nuts onto a sheet pan and toast in the oven for 7-10 minutes, just until the nuts begin to turn golden brown.

In a heavy bottomed saucepan, combine the sugar, water, butter and corn syrup over medium low heat. Stir until butter is melted and sugar is dissolved. Once mixture begins to boil, insert a candy thermometer and cook to 300°F, while stirring occasionally. This will take about 12-15 minutes. As it cooks, it will caramelize and turn golden brown.

While caramel cooks, prep the rest of your ingredients and tools and have them ready and nearby.

As soon as the temperature reaches 300°, immediately stir in the baking soda, which will cause the caramel will foam. Moving quickly, stir in the nuts and dump onto a non stick sheet pan or a sheet pan lined with a silicone baking mat or parchment paper. Use the back of a spoon to spread out the mixture as thin as you can (mixture will be thick). Sprinkle generously with salt.

Let sit for 30 minutes until cool. Break brittle into small chunks with your hands.

Brittle will keep, stored in a cool dry place, for up to a few weeks.