Preheat the oven to 270°F.
Beat the egg whites, first on slow speed and when some bubbles form, increase the speed. Once the egg whites are firm, reduce the speed and slowly add granulated sugar, incorporating everything well. Beat for about 3 to 5 minutes. Lastly, manually incorporate 2.5 oz of powdered sugar and maqui berry powder.
Form the nests with a piping bag on parchment paper or Silpat and bake for 35 to 45 minutes.
Take out and allow to cool.
For the filling, whip the cream with powdered sugar until firm. Then incorporate half of the blueberries into the cream and fill every nest.
Top the nests with some blueberries on top and dust some maqui berry powder.