In a medium bowl, combine the graham crumb, melted butter and sugar. Stir until evenly combined.
Press the graham cracker mix evenly to the bottom of your jars or pan. Place in refrigerator.
For the filling
In a large bowl, combine cream cheese, lemon juice and lemon zest. Beat with an electric mixter until smooth.
In a separate bowl, combine whipping cream, confectioners' sugar and vanilla. Beat with an electric mixer until still peaks form.
Fold the whipped cream into the cream cheese mixture.
Pour filling evenly into jars or single pan. Refrigerate 6 hours.
For the topping (optional)
Combine butter, confectioners's sugar and lemon juice in a large bowl. Beat with an electric mixer until smooth, adding whipping cream 1 tablespoon at a time until desired consistency is achieved.