Remove raspberries from package and place in a 1-quart casserole.
Microwave at LOW 2 to 3 minutes.
Blend sugar and cornstarch.
Stir into raspberries.
Add jelly and lemon juice.
Microwave at HIGH 3 to 5 minutes.
Stir well after 3 minutes.
Cool before serving over cheesecake, ice cream, fruit, or cake.