Using a large spoon, drop about one-sixth of the mixture onto the prepared baking sheet. Using the back of the spoon and working in a circular motion, spread the dollop into a disk about 4 inches wide and make a depression in the center of each. Continue with the remaining meringue mixture. Bake the meringues until they are no longer tacky on the surface and are very lightly golden, about 1 hour. Turn off the oven and prop open the oven door about 1 inch (2.5 cm). Let cool completely in the oven before serving, about 2 hours.