Coat 2 (6-ounce) souffle dishes or custard cups with cooking spray. Sprinkle dishes evenly with 1 tablespoon sugar, carefully shaking to coat bottom and sides of each dish; set aside.
Combine 1 tablespoon sugar, milk, and flour in a non-aluminum saucepan, stirring with a wire whisk until blended. Cook over medium heat, stirring constantly, until thickened and bubbly. Remove from heat.
Beat egg yolk until thick and pale. Gradually stir about one-fourth of hot mixture into yolk; add to remaining hot mixture, stirring constantly. Stir in orange extract and orange rind; set aside.
Beat egg white, 1/2 teaspoon powdered sugar, and cream of tartar in a bowl at high speed of an electric mixer until stiff peaks form. Fold egg white mixture into orange mixture. Spoon into prepared dishes. Bake at 375° for 15 minutes or until puffed. Sift remaining 1 teaspoon powdered sugar over souffles. Garnish with orange zest, if desired. Serve immediately.