1 cup margarine, softened
1/2 cup white sugar
1 egg
1 teaspoon dried sage
2 tablespoons prepared horseradish
1 1/2 teaspoons dried minced onion
1 teaspoon salt
1 teaspoon garlic powder
2 tablespoons white sugar
1 teaspoon dried parsley
Preheat oven to 350 degrees F (175 degrees C).
In a medium bowl, cream together margarine, sugar, egg, sage, horseradish, onion, salt, garlic powder and white sugar. Mix well and press into the bottom and up sides of a 9x13 inch baking dish.
Bake at 350 degrees F (175 degrees C) for 1 hour, or until browned.
Meanwhile, gently grease a medium baking sheet. Place ham mixture on the baking sheet.
In a medium bowl, mix potato mixture with remaining 3 1/2 cups graham cracker crumbs, one cup horseradish, 1/2 cup parsley and 1 cup minced onion. Spread mixture evenly over the crust. Sprinkle remaining 3 1/2 cups graham cracker crumbs on top of crust.
Bake uncovered for 30 to 35 minutes in preheated oven, or until casserole is golden brown. Cool completely before cutting into 1/2 inch squares.