buttermilk sweet potato pie recipe

Ingredients:

2 medium sweet potatoes

1 refrigerated pie crust

4 tablespoons unsalted butter, melted

1 1/2 tablespoons lemon juice

1/2 teaspoon nutmeg

1/2 teaspoon cinnamon

1/2 teaspoon salt

3 large eggs, separated

1/2 cup granulated sugar

2 tablespoons packed light brown sugar

2 tablespoons all-purpose flour

3/4 cup buttermilk