Lay saltine crackers in the bottom of an 11 x 17 cookie sheet Heat butter and brown sugar together and cook until it reaches 250-268 with a candy thermometer Remove from heat and stir in cashews Pour over crackers and spread well Sprinkle with chocolate chips and place in oven at 400 for 5 minutes Remove and spread chocolate with a knife Refrigerate at least 30 minutes or until hard Break into pieces