This is an easy yet authentic-tasting coffee milk pudding recipe that uses a 500ml milk carton as a mold. Heat and mix powdered gelatin softened in water, milk, sugar, instant coffee, and liqueur (optional) in a saucepan, then cool it in an ice bath. Pour the mixture into the milk carton, straining it as you go, and refrigerate overnight until firm. Once set, use a warm towel to remove the pudding from the milk carton and enjoy its wobbly, rich texture and flavor. This dessert is perfect for a home café or as a gift, and even beginners can make it without fail.