In A Large Skillet Over Medium Heat, Cook The Beef, Celery And Onion Until Meat Is No Longer Pink And Celery Is Tender; Drain. Stir In The Flour, Salt, Oregano And Pepper Until Blended. Add Tomato Sauce And Peas; Simmer For 5 Minutes. Transfer To A Greased 13-In. X 9-In. X 2-In. Baking Dish. Separate Biscuits; Arrange Over Beef Mixture. Sprinkle With Cheese. Bake, Uncovered, At 350 Degrees F For 20 Minutes Or Until Biscuits Are Golden And Cheese Is Melted.