In a medium saucepan, combine chopped fresh rhubarb, sliced strawberries, granulated sugar, and cornstarch. Cook over medium heat for about 10 minutes, stirring frequently until the mixture bubbles and thickens. Remove from heat and let it cool completely.

In a large mixing bowl, beat the heavy cream with vanilla extract until soft peaks form, about 3-5 minutes. Be careful not to overbeat.

In another bowl, beat the cream cheese until smooth, then gradually fold in the whipped cream until just combined.

In the prepared graham cracker crust, layer cooled fruit mixture and creamy mixture alternately, finishing with a cream layer on top.

Cover with plastic wrap and refrigerate for at least 2 hours until set.

Once chilled, slice into generous portions and serve.