2 (15 oz.) Ricotta cheese
2/3 c. sugar
1/3 c. flour
6 eggs
1/4 tsp. cinnamon
2 tsp. orange zest
2 tsp. vanilla extract
1/8 tsp. salt
1 3/4 c. fine crushed graham cracker crumbs
1/4 c. finely chopped nuts
1/2 tsp. cinnamon
1/2 c. melted butter

Set rack in middle of oven. Butter and flour a 9 1/2-inch spring-form pan (tap out excess flour). Mix graham cracker crumbs, walnuts, 1/2 teaspoon cinnamon and melted butter together. Press in sides and bottom of pan.

Place Ricotta in large mixing bowl; stir it as smooth as possible with a rubber spatula. Stir the sugar and flour together thoroughly into the Ricotta. Stir in eggs, one at a time. Blend vanilla, 1/4 teaspoon cinnamon, orange zest and salt. Pour batter into prepared pan.

Bake at 350°F in center of oven for approximately 1 1/4 to 1 1/2 hours until a light golden color. It's done when an inserted knife comes out clean.