Lemon Lemon Loaf

INGREDIENTS

• 1/4 cup fresh lemon juice
• 1/2 cup sour cream, at room temperature
• 1/4 cup grated lemon zest (from about 4 lemons)
• 4 to 6 tablespoons fresh lemon juice
• 1 1/2 cups cake flour
• 1/3 cup sugar
• 2 teaspoons baking powder
• 8 large eggs, at room temperature
• 2 cups (4 sticks) unsalted butter, melted and cooled
• 2 1/4 cups sugar
• 1/4 teaspoon baking soda
• 1 teaspoon salt
• 2 teaspoons pure vanilla extract
• 1 1/2 cups all-purpose flour
• 2 cups confectioners' sugar, sifted, or more if needed
• 1/3 cup fresh lemon juice