makes 1 cup
Preheat oven to 250°F. In large frying pan, combine sugar and water over medium-high heat and cook until sugar dissolves and syrup comes to a boil. Add the walnuts, butter, a pinch or two of salt, and cook, stirring constantly, until syrup coats the nuts and almost no liquid syrup is left in the pan.
Line a sheet pan with a Silpat or parchment. Spread the nuts out on the prepared baking sheet and put in the oven to toast for about 15 minutes. Store air tight for up to 2 weeks.
Allow to cool 10 minutes before tasting or you will burn your mouth. This time also allows the nuts to crisp.