Ingredients

　　2 (14-ounce) cans sweetened condensed milk

　　Empty milk into the top of a double boiler or a heatproof bowl over a pan of simmering water. Cover with a tight-fitting lid. Cook, stirring every 10 to 15 minutes, until the milk is thick and amber in color, about 5 hours. Remove from heat, and beat with a wooden spoon to smooth out. Transfer to a clean bowl, and refrigerate several hours or up to 3 days.

　　Martha Stewart's Cookies