Please choose the correct solution to the question: How to Make the Filling for North Carolina Lemon Pie

Solution1: To make filling for North Carolina Lemon Pie, mix condensed milk, egg yolks, heavy cream and lemon zest in a bowl.

Solution2: To make filling for North Carolina Lemon Pie, separate condensed milk, egg yolks, heavy cream and lemon zest in a bowl.

Answer format: solution1/solution2