Ingredients

• 1 cup all-purpose flour
• 1 tablespoon sugar
• ⅛ teaspoon salt
• 1 tablespoon butter
• 3 tablespoons neutral oil, such as canola or avocado
• 1-2 tablespoons ice water
• 1¼ cups sugar
• ¼ cup cornstarch
• ¼ teaspoon salt
• 1½ cups boiling water
• ½ cup lemon juice
• 1½ tablespoons freshly grated lemon zest
• 1 large egg
• 1 large egg white
• 2 teaspoons butter
• 3 large egg whites
• ¼ teaspoon cream of tartar
• pinch of salt
• ½ cup sugar
• 1 teaspoon vanilla extract