Cut oranges in half and use juicer to squeeze out the juice. Reserve the juiced orange peel halves as the cups for the jello shots.
In medium mixing bowl, pour in your orange juice. Sprinkle with unflavored gelatin. Gently stir. Let sit 2 minutes. Pour boiling water over that. Add orange Jello and stir until dissolved. Pour in Aperol and Prosecco. Stir. Line baking sheet with 8 orange halves. Pour some of the mixture into each orange half. Refrigerate 4 hours or overnight. Slice and serve.
Notes
If desired, add vodka to taste to liquid mixture before chilling in refrigerator.