In a large mixing bowl combine the powdered sugar, cornstarch, egg white, lemon juice and whisk until all the ingredients are combined well.
Add the cranberries and mix again. Next, place about a third of the coated cranberries into a sieve, spread them evenly and let the sugar mixture drain for a few seconds.
Then, place the cranberries into a bowl with powdered sugar and, using a spoon, mix them together. The goal is to coat each cranberry with a thick layer of powdered sugar. Let the cranberries sit for a couple of minutes, shake them one more time and transfer into a baking sheet covered with parchment paper. Repeat the process with the rest of the cranberries.
When all the cranberries are coated with powdered sugar, place the baking sheet into an oven that has been preheated to 170°F degrees (75°C), leave the door slightly open and bake them for 50-60 minutes. Turn the oven off and let them cool inside the pre-opened oven.