Grease a 13x9" pan with unsalted butter and set aside. To make filling, in food processor or blender, combine egg yolks, 1/3 Cup sugar, 2 teaspoons vanilla, 1 Cup Mascarpone or Cream cheese, 1-1/2 Cups cottage cheese, and 1 Tablespoon lemon juice; process or blend until smooth. Set aside.
To make blintz batter, in large bowl, combine 1 Cup sour cream, 1/2 Cup Mascarpone or Cream cheese, eggs, orange juice, 3 Tablespoons . lemon juice, melted butter, and 1/3 Cup sugar; beat well until combined. Add flour, baking soda, 1/2 teaspoon cinnamon, baking powder, and 1 teaspoon vanilla, and beat until smooth with electric mixer.
Pour half of the orange juice batter into prepared pan. Drop the cottage cheese mixture by small spoonfuls over batter, then spread evenly to cover. Pour remaining batter over filling. Cover and refrigerate overnight.
In the morning, heat oven to 350º F. In small bowl, combine 3 Tablespoons sugar with 1 teaspoon cinnamon and sprinkle over the casserole. Bake casserole, uncovered, for 50-65 minutes until puffed and light brown. Cut into squares and serve with A fruit sauce, powdered sugar and maple syrup or your favorite topping..