New York Cheesecake Cookies

INGREDIENTS

• 1/2 teaspoon vanilla extract
• 1 cup flour
• 1/4 cup granulated sugar
• 1 stick (8 tablespoons) unsalted butter, softened
• 2 teaspoons lemon zest
• 1 egg, separated
• 1/2 cup packed brown sugar
• 1 1/2 teaspoons baking powder
• 3 ounces cream cheese, softened
• 1 1/4 cups finely crushed graham crackers (1 sleeve)