|Watermelon||3 Cup (48 tbs) (small pieces, seeded)|
|Lemon juice||2 Tablespoon|
|Sugar||1⁄2 Cup (8 tbs)|
|Envelope of gelatin||1 (unflavored)|
|Water||1⁄2 Cup (8 tbs)|
1. Place watermelon, about half at a time, in an electric-blender container; cover. Whirl till smooth and liquid. (You should have about 2 cups.) Pour into medium-size bowl; stir in lemon juice. (If you do not have a blender, press the melon through a sieve into a bowl.)
2. Mix sugar and gelatin in a small saucepan; stir in the water. Heat slowly, stirring constantly, until gelatin dissolves. Cool slightly; stir into watermelon mixture. Pour into a 9x9x2-inch pan.
3. Freeze about 1 1/2 hours, or until firm around edges.
4. Spoon into a large bowl; beat until smooth; return to pan. Freeze several hours longer, or until firm.