Line a large baking pan or a cookie sheet with parchment, foil, or a silicone mat. Lightly grease the parchment if using. Set aside.

In a heavy medium saucepan over medium-high heat, combine together the sugar, water, butter, corn syrup, and salt. Cook, stirring, until the butter melts and the sugar dissolves, then raise the heat to high and boil without stirring, occasionally brushing down the sides of the pan with a wet pastry brush, until the mixture turns deep golden brown in color and registers 350F on a candy thermometer.

Remove from the heat and stir in the pine nuts with a wooden spoon. Make sure the caramel coats all the nuts. Turn the mixture out onto the prepared sheet pan and, using a buttered heat-resistant spatula, spread it so the nuts are in a single layer. Let the brittle cool completely before breaking it into pieces. Keep in an airtight container in a cool, dry area for up to 2 weeks.