Step 1 Peel the oranges with a vegetable peeler, eliminating any white pith. Combine the peel and sugar in a food processor and process 2 to 3 minutes.
Step 2 Place the orange juice in a nonaluminum saucepan. Add the peel-sugar mixture and bring just to a boil, skimming off any foam. Simmer 3 to 4 minutes to reduce slightly.
Step 3Mix in the blueberries and cook 1 minute. Serve warm.