Macaroni and Cheese Au Gratin

This version of Macaroni and Cheese adapted from my mother in law is my favorite, its a little different from the regular mac and cheese in texture. I use a cheese called Kasher imported from Turkey which can be found in a Mediteranean market. If you can't find this cheese you can use provolone.

1lb of ziti
1 stick butter
2 tablespoons flour
1 cup milk
3 eggs
1 lb ricotta cheese
1 lb feta cheese crumbled
1/2 cup shredded provolone or Turkish kasher cheese
1/4 cup parmesan cheese
1 teaspoon salt
1/4 teaspoon pepper

Boil the macaroni drain and set aside. Melt the butter in a sucepan. Add the flour stir until smooth. Reduce to simmer and stir in the milk. Add the eggs one at a time stirring without stopping until the eggs are all added to the mixture, remove from heat and set aside. In a bowl mix together ricotta cheese, crumbled feta cheese and half of the shredded kasher cheese. Stir in the cheese mixture to the cream mixture.
Butter a 9x12 pan and about 4 inches high.
Mix half of the cheese mixture with the pasta. Add the remaing half of the cheese mixture on top of the pasta. Add the parmesan cheese and than the remaining shredded kasher cheese.