Combine 2 tablespoons grated orange zest and 1 ½ cups strained orange juice in a small nonreactive saucepan and simmer until reduced to just under ½ cup. Let cool completely, then add 1 tablespoon strained lemon juice. Prepare Lemon or Lime Cold Soufflé or Bavarian Cream, substituting the orange reduction for the lemon or lime zest and juice.