Preheat oven to 350*. On a jelly roll pan (cookie sheet with short sides!) Line with foil, then cover with non-stick spray. Lay out a single layer of saltine crackers. In the saucepan, add butter and sugar. Melt butter, stir in sugar and then bring mixture to a roiling boil. Make sure to not boil overmuch, as the butter will scorch and turn brown. Once boiling, remove from heat. Pour liquid over the crackers, attempting to cover all. Try to ensure the crackers are still in a single layer. Bake at 350* for 10 minutes. Crackers should be slightly brown. While still hot, sprinkle chocolate chips over the top. They will melt. Spread them across the tops of the crackers. If desired, you can add optional toppings of crushed candy canes, pretzels, nuts, sprinkles, whatever you like, but they are just as good without. Refrigerate them for 2 hours. When they come out, take a sharp knife and cut along the lines of the crackers. So good!!