Nutrition per serving may change if servings are adjusted.
½ cup sugar (see Tips)
1 tablespoon cornstarch
2 egg whites, at room temperature
¼ teaspoon cream of tartar
¼ teaspoon lemon extract
⅛ teaspoon salt
Yellow Cream Filling
½ cup light cream cheese, softened
¼ cup light sour cream
2 tablespoons powdered sugar (see Tips)
½ teaspoon lemon zest
4 to 6 drops yellow food coloring
To prepare cookies: Preheat oven to 300°F. Line two large cookie sheets with parchment paper. In a small bowl stir together sugar and cornstarch.
In a medium bowl combine the next four ingredients (through salt). Beat with a mixer on medium to high until soft peaks form (tips curl). Gradually add sugar mixture, about 1 Tbsp. at a time, beating on high until stiff peaks form (tips stand straight).
Spoon egg white mixture into a decorating bag fitted with a large round tip. Pipe 3-inch circles, ¼ to ½ inch thick, onto the prepared cookie sheets, leaving 1 inch between circles.
Place cookie sheets on separate oven racks; bake 10 minutes. Turn off oven; let cookies dry in oven with door closed 1 hour. Remove; let stand on wire racks just until cool (see Tips).
Meanwhile, prepare filling: In a medium bowl, beat cream cheese with an electric mixer on medium speed until smooth. Beat in sour cream, powdered sugar and lemon zest. Stir in food coloring to reach desired color.
Before serving, spoon the filling into a decorating bag fitted with a large round tip. (Or fill a heavy resealable plastic bag with filling; snip a small hole in one corner of the bag.) Pipe filling onto bottoms of half of the cookies, using 2 tsp. for each cookie. Top with the remaining cookies, bottom sides down.
Tips: Sugar Substitutes: We do not recommend using sugar substitutes for this recipe.
The cookies can quickly become tacky, especially if the weather is humid. If not serving immediately, store unfilled cookies in an airtight container at room temperature up to 3 days.