Heat the orange juice with the sugar in a saucepan, stirring until the sugar dissolves. Remove from the heat.
Lightly beat the eggs and egg yolks with a fork in a large bowl. Beating constantly, gradually add the citrus mixture in a slow, thin, steady stream and beat until well combined. Strain the mixture into another bowl, then ladle it into eight 6-ounce ramekins. Place the ramekins in a large shallow roasting pan and place it on an oven rack that's pulled partway out. Carefully pour enough boiling water into the pan to come halfway up the sides of the ramekins.
Bake the orange flan for 30 minutes, or until the tops are set. Take the ramekins out of the pan and let cool to room temperature. Cover with plastic wrap and refrigerate at least 8 hours or until ready to serve.