Squeeze juice from blood oranges and strain the pulp.
Fill each champagne flute with about 3 oz of blood orange juice. Champagne flutes are usually 6 oz so fill it up half way.
Fill the glass up with champagne, pouring it slowly and letting foam go down.
NOTE: This recipe is calculated for a bottle of champagne. You will get 8 mimosas out of a bottle of champagne if each mimosa contains about 3 oz of champagne.