Combine flour, pecans, melted butter, and sugar in a small bowl.

Press the mixture into a greased 13x9 inch baking dish.

Bake at 350 degrees F (175 degrees C) for 18-20 minutes, or until golden brown.

Cool the crust completely on a wire rack.

In a large saucepan, combine brown sugar and cornstarch.

Stir in chopped rhubarb until combined.

Bring the rhubarb mixture to a boil over medium heat, stirring frequently.

Reduce heat and simmer for 4-5 minutes, or until the mixture thickens.

Remove the saucepan from heat and let the rhubarb filling cool.

Stir in the sliced strawberries.

In a small mixing bowl, beat cream cheese and confectioners' sugar until smooth.

Gently fold in 1 cup of whipped cream.

Spread the cream cheese mixture over the cooled crust.

Top the cream cheese layer with the cooled rhubarb-strawberry mixture.

Spread the remaining whipped cream over the rhubarb filling.

Refrigerate the dessert for at least 3-4 hours before serving.

Garnish with additional brown sugar before serving, if desired.