Meanwhile, in a large mixing bowl, stir ricotta with a rubber spatula until it reaches an extremely smooth consistency. Add the sugar and flour into the ricotta, mixing thoroughly.
Stir in the eggs one at a time. Next add the vanilla, cinnamon, lemon zest, and salt. Mix well. Pour batter into crust.
Bake in the center of the oven for about 75-90 minutes at 300 degrees until the cake is a light golden color. When it's ready, the center should be fairly firm, and the point of a sharp knife inserted in the center will come out clean.
Cool cake on a wire rack. Cover, and chill until serving time.