Combine the first 3 ingredients in a bowl; stir well, and set aside. Beat 2 egg yolks in a large bowl at high speed of a mixer for 2 minutes. Gradually add 1/2 cup sugar, beating until thick and pale (about 2 minutes). Add 2 tablespoons water and vanilla, beating at low speed until blended. Add the flour mixture, and beat well.
Beat 3 egg whites at high speed of a mixer until foamy. Gradually add 1/4 cup sugar, 1 tablespoon at a time, beating until stiff peaks form. Gently stir one-fourth of egg white mixture into batter; gently fold in remaining egg white mixture.
Pour batter into an 8-inch square baking pan coated with cooking spray. Bake at 350F for 20 minutes or until cake springs back when touched lightly in center; let cool 5 minutes in pan on a wire rack. Loosen cake from sides of pan, using a narrow metal spatula, and turn out onto wire rack; let cool completely.
Place cake, bottom side up, on an ovenproof platter. Spread jam over cake. Cut container of frozen yogurt in half; reserve one half for another use. Cut remaining half of frozen yogurt into 1-inch-thick slices. Arrange frozen yogurt slices over jam; cover and freeze at least 15 minutes. (You can assemble recipe to this point one day ahead and store, covered, in the freezer.)
Beat 4 egg whites and cream of tartar at high speed of a mixer until stiff peaks form; set aside. Combine 1/3 cup sugar and 3 tablespoons water in a saucepan, and bring to a boil. Cook, without stirring, until candy thermometer registers 238F. Pour sugar mixture in a thin stream over egg whites, beating at high speed. Spread meringue over yogurt slices and around sides of cake (yogurt and cake should be completely covered with meringue). Bake at 500 degrees for 2 minutes.