Melt the butter and combine well with the graham cracker crumbs. Use a spoon and divide the crumb mixture between 12 -4oz. Mason Jars, and then press the crumbs down with the back of a spoon to create the cheesecake base.
Next, combine the cream cheese, sweetened condensed milk, lemon juice, and vanilla in a stand mixer with the paddle attachment, beating until the mixture is smooth and thoroughly combined.
Divide the cheese cake filling mixture between the 12 mason jars. Refrigerate the mason jars, until the cheesecake is set, about ½ hour.
Once the cheesecake is set, and able to support the jam topping, spoon about a teaspoon over the cheesecakes. Don't use too much, since jam is sweeter than pie topping which is usually used as a cheesecake topping.
Refrigerate until you are ready to serve. Just before serving, top each cheesecake with some whipping cream, and add a fresh berry. Enjoy!