1 lb. cream cheese, softened
1 lb. Ricotta cheese
1 1/2 c. sugar
4 l.g eggs, room temperature
1/2 stick unsalted butter, melted and cooled
3 tbsp. flour
3 tbsp. cornstarch
2 1/2 tsp. vanilla
2 c. sour cream

In a large bowl with mixers, cream together cream cheese, Ricotta cheese, and sugar. Beat in eggs, one at a time, beating well after each addition. Add butter, flour, cornstarch and vanilla. Beat mixture until well combined. Fold in sour cream.

Turn into ungreased springform pan. Bake in the middle of a 325 degree oven for 1 hour. The cake will be soft in the center - do not open oven door. Let cake remain in oven for 2 hours. Remove sides of pan and put on a cake plate. Add topping (if desired) after cheesecake is cooled.