1/2 cup butter
1 cup all-purpose flour
1 cup bread flour
2 eggs, beaten
1 teaspoon white sugar
3 cups shredded Cheddar cheese
1/2 cup chopped onion
2 teaspoons minced fresh parsley
1/4 teaspoon salt
3 cups shredded Swiss cheese
Preheat oven to 375 degrees F (190 degrees C).
Pour butter into a small mixing bowl. Stir in flour, divide into 4, and knead.
Transfer butter mixture into flour and dough, coating thoroughly. Roll dough into a 1/4-inch thick and fill-out to 1/4 inch width.
Turn out onto a lightly floured surface. Roll dough into a 2-inch thickness. Continue kneading until smooth. Cut into 10 squares. Place at least 1 teaspoon of garlic powder into each square.
Place potatoes on an ungreased baking sheet. Brush with olive oil. Bake in the preheated oven 25 minutes.
To make the sauce: In a small mixing bowl, whisk together 2 cups Cheddar cheese, onion, parsley, salt, Swiss cheese, parsley and cheese. Mix enough to coat well.