Preheat oven to 325F.
Wash rhubarb then cut the ribs in half and then lengthwise so that you get thing strips. Dice to 1/4-inch cubes.
Combine all of the ingredients except the rhubarb in a blender and blend until very smooth. Place crust in a 6- to 8-inch tart ring. Fill crust half of the way with diced rhubarb making sure to reserve a little bit for the top. Add the liquid filling until it rises just below the crust edge. Bake for 25-35 minutes until the crust is golden brown. To make sure it's completely baked, use an offset spatula to lift from the bottom.
Note: you can substitute orange juice for vanilla liquor!