Preheat oven to 300°F. Line 2 shallow baking pans with parchment paper; set aside.
Beat egg whites and cream of tartar in large bowl with electric mixer or stand mixer with whisk attachment on high speed until stiff peaks form, about 1 to 2 minutes.
Beat cream cheese in separate large bowl on medium speed until smooth. Add egg yolks, one at a time, beating until completely smooth. Gently fold egg white mixture into yolk mixture. Using a 1/4-cup measuring cup, scoop batter onto prepared baking sheets about 2-inches apart, spreading each scoop into a 4-inch circle.
Bake 25 minutes or until golden brown and center is completely set. Cool on baking pans 5 minutes. Remove to wire racks; cool completely.
Try these twists:
• Italian Herbs & Cheese: Prepare as directed, stirring 3 tablespoons grated Parmesan cheese, 1/2 teaspoon McCormick® Perfect Pinch® Italian Seasoning and 1/4 teaspoon McCormick® Garlic Powder into egg yolk mixture until well blended.
• Cinnamon Vanilla: Prepare as directed, stirring 1 tablespoon confectioners’ sugar, 1/2 teaspoon McCormick® Ground Cinnamon and 1/2 teaspoon McCormick® Pure Vanilla Extract into egg yolk mixture until well blended.
• Chocolate: Prepare as directed, stirring 1 tablespoon confectioners’ sugar, 1 tablespoon unsweetened cocoa powder and 1/2 teaspoon McCormick® Pure Vanilla Extract into egg yolk mixture until well blended.