3 lb ripe grapefruit
2 apples
1 box Certo crystals
2.2 lb sugar
Peel grapefruit and remove skin from segments.
Peel and cut apples into thin wedges.
Mix. Sprinkle Certo crystals over it.
Cover with Saran wrap, punch a slot at each corner and cook at
level 10 for 20 minutes. Stir half way.
Remove from oven, add sugar, mix well and place into oven,
uncovered, for 25 more minutes. Stir half way through.
Pour into jars sterilized in a conventional oven at 250 F for 30
minutes.
It produces 1 qt marmalade.