Add the eggs, and stir well. Add the flour, and stir until all the lumps are gone. Stir in the vanilla. Fold in about 2/3 of the Oreos. Spread the mixture into the baking dish. Sprinkle the remaining Oreos on top and add a few Halloween sprinkles for extra festiveness. Bake approximately 40 to 50 minutes, being cautious not to overcook. Cool completely before slicing into squares. Store in an airtight container.