Heat oven to 350. Grease 10 inch deep dish pie pan or 9 inch square pan with margarine. In medium saucepan, bring water to a boil; add potato slices. Return to a boil; boil 4 minutes. Drain. Arrange partially cooked potato slices over bottom and up sides of greased pan to form crust.

In medium bowl, combine contents of seasoning mix envelope, salt, milk, hot pepper sauce and eggs; stir until smooth.Stir in oni and cheese; pour into crust. Bake at 350 for 28 to 35 minutes or until center is set. Let stand 10 minutes before serving. To serve cut into wedges or squares.