Frozen Watermelon Mousse

Place watermelon in container of an electric blender, and process until smooth. Reserve 2 1/4 cups puree, discarding any remaining puree. Combine gelatin and 1/4 cup watermelon puree; set aside.

Bring remaining 2 cups puree to a boil in a small saucepan. Remove from heat; add gelatin mixture, and stir until gelatin dissolves. Stir in sugar and lemon juice, and chill mixture until consistency of unbeaten egg white.

Fold whipped cream into chilled watermelon mixture. Spoon into a lightly oiled 6-cup mold. Cover and freeze 8 hours or until firm; unmold onto serving plate. Serve immediately.