I have been wanting to try a meringue cookie forever now… I never have before! If there is ever an option of sugar cookies or chocolate I tend to pick that over meringue.
Beat egg whites in large bowl with electric mixer on medium speed until frothy. (If using a freestanding mixer, use wire whisk attachment.) Add cream of tartar; beat until soft peaks form. Increase speed to medium-high.
Place the meringue into a pastry bag fitted with a 2D, 1G, or large star tip. Slowly pipe out in a circle for the small meringue cookie onto a parchment-lined cookie sheet. For the tree, pipe out a small circle then continuously make smaller circles working your way up.
Bake both sheets of meringues at the same time 45 minutes. Turn oven off. Let meringues stand in oven 1 hour or until completely cooled.