Mist an 8-inch round cake pan with nonstick cooking spray.

Bake the cake in prepared pan according to directions on box, adding an additional egg and lemon extract to batter.

Let cake cool in pan for about 10 minutes, then remove from pan and cool completely.

Prepare pudding according to directions on box, using 1 1/2 cups milk and adding vanilla extract. When pudding is ready and still hot, cover with plastic wrap to prevent skin from forming. Refrigerate until chilled.

Split cake into two layers, cover one layer with pudding and replace the top layer.

Make glaze. Blend all ingredients in mixing bowl. Beat until smooth. Glaze only the top layer of the cake. This cake must be kept refrigerated.