Preheat oven to 350°. In a medium bowl, combine flour and brown sugar; stir in melted butter until crumbly. Reserve 1/2 cup crumb mixture for topping; press remaining crumb mixture into an ungreased 13x9-in. baking pan.
In a large bowl, mix rhubarb and granulated sugar; sprinkle with cinnamon. Spoon over crumb mixture.
In a small bowl, beat cream cheese, vanilla and eggs until smooth. Pour over rhubarb mixture.
Sprinkle with reserved crumb mixture. Bake at 350° for 30 minutes or until golden brown and bubbly. Cool completely before cutting into bars.
Interesting Facts
Rhubarb is not a fruit, but a vegetable.
Rhubarb is a good source of Vitamin C and dietary fiber.
Rhubarb has a tart flavor, so it's often paired with sugar or other sweeteners.
Rhubarb is believed to have originated in China, and has been used for medicinal purposes for centuries.