Fools are desserts that are traditionally made with gooseberries and custard. Nowadays, whipped cream and virtually any stewed fruit can be blended to create this cloudlike dessert that, as the name suggests, just about anyone can make.
Combine the first 3 ingredients in a medium saucepan, and bring to a boil. Cover, reduce heat, and simmer 10 minutes or until liquid almost evaporates. Add sugar and lemon juice, and cook over medium-high heat for 8 minutes or until slightly syrupy. Place the pineapple mixture in a blender; process until smooth. Pour the mixture into a bowl; cover and chill.
Reserve 1/4 cup of chilled pineapple mixture. Fold the whipped topping into the remaining chilled pineapple mixture. Spoon 1/2 cup of the pineapple mixture into each of 6 glasses, and chill. Top each serving with 2 teaspoons of the reserved pineapple mixture before serving.