In a medium-sized saucepan, stir together the sugar, corn syrup, and milk over low heat. Add the walnut pieces, stirring to make sure they are entirely coated in the sugar mixture. Increase heat to medium and bring to a boil. Let boil for several minutes, stirring occasionally, as the sugar darkens. When it has browned on the edges, remove from the heat.
Pour the walnut mixture onto a greased baking sheet and cool. Separate the walnuts and store in an airtight container or plastic bag. (They will last for about 1 week.)
Yields 1 cup
Caramel flavoring is made by heating granulated sugar until it “caramelizes,” becoming a thick, golden syrup. This recipe also works well with pecans.