Slice 8 ounces fresh rhubarb (measure 1 1/2 cups). If using frozen, thaw 1 1/2 cups sliced frozen rhubarb; set aside. In a small saucepan, stir together 1/3 cup sugar, 1 tablespoon water, 1 tablespoon finely chopped crystallized ginger and, if you like, 1 strip orange peel. Bring to boiling; stir in rhubarb. Return to boiling; reduce heat. Simmer, covered, over low heat for 10 to 12 minutes or until rhubarb is very tender. Remove the orange peel, if using. If using fresh rhubarb, stir in 1 to 2 drops red food coloring, if desired. Cool to room temperature. Place rhubarb mixture in a food processor or blender. Cover and process or blend mixture until pureed. Transfer to a bowl. Chill, covered, about 2 hours or until chilled. Proceed as directed in Step 2.