Preheat oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking pan. Chill a metal bowl in refrigerator.
Mix flour, pecans, butter, and white sugar in a bowl and press the mixture into the bottom of the prepared baking pan.
Bake the crust in the preheated oven until golden brown, 18 to 20 minutes; cool in pan on wire rack.
Mix 1 cup brown sugar, corn syrup, and cornstarch in a saucepan; stir in rhubarb. Bring the rhubarb mixture to a boil; reduce heat and cook, stirring often, until thickened, 4 to 5 minutes. Let the filling cool and stir in strawberries.
Beat cream cheese with confectioners' sugar in a bowl until smooth.
Pour heavy cream into chilled metal bowl and whip with an electric mixer until fluffy and the cream holds soft peaks, about 3 minutes. Fold 1 cup of the whipped cream into the cream cheese mixture; reserve remaining whipped cream.
Spread the cream cheese mixture over the cooled crust and top with the rhubarb mixture; spoon the remaining whipped cream over rhubarb layer. Refrigerate until set and thoroughly chilled, 3 to 4 hours; sprinkle with 2 tablespoons brown sugar.