Ruby Red Grapefruit Marmalade

1. With vegetable peeler, remove thin outer zest from grapefruit and lemons. With sharp knife, cut zest into very fine strips (1 to 2 inches long). You should have about 1 1/2 cups grapefruit zest and 1/3 cup lemon zest. 2. In large enamel or stainless steel saucepan, combine zest and water. Bring to a boil over high heat; reduce heat, cover and boil gently for 20 minutes. 3. Remove and discard remaining white pith from grapefruit and lemons. Cut grapefruit and lemons in half, then into pieces; remove and discard seeds. Put pieces in food processor or blender and process until finely chopped (about 4 1/2 cups). 4. Add to zest and bring to a boil over high heat; reduce heat, cover and boil gently for 10 minutes, stirring frequently. 5. Add sugar to fruit. Return to a boil over high heat and boil rapidly, uncovered, for about 30 minutes or until mixture gels on a cold plate or a candy thermometer registers 220 F, stirring frequently. Remove from heat. Skim off foam. Stir and skim a few minutes. 6. Ladle marmalade into hot sterilized jars, leaving 1/4-inch headspace. Process in boiling water bath for 5 minutes.