Prepare glass jars or plastic containers with lids by washing them in hot soapy water or in a dishwasher. Recipe makes 5 cups of jam. Number of jars you'll need will depend on the size of your jars.

Remove the colored part of peel from the oranges and grapefruit using a vegetable peeler or zester. I like to use the kind shown in the photos above. It works perfectly to remove small strips of zest. If you use a vegetable peeler, cut the peel into thin slivers, or finely chop. Peel and discard the remaining white part of peel from the oranges.

Coarsely chop the orange and grapefruit, discarding any membranes and saving the juice. Mix fruit and juice with the zest and lemon juice. Measure 2-⅓ cups of the fruit mixture into a large microwave-safe bowl. If you have extra, discard or save for another use. (See note.) Add sugar and stir for 1 minute.

Microwave on high for 3 minutes. Stir well and microwave again for another 2 minutes. Stir until all sugar crystals are dissolved, another minute or two. Taste, and if mixture is still "grainy," microwave again for another minute or two to dissolve any remaining sugar crystals.

Combine the water and pectin in small saucepan. Bring to boil on high heat, stirring constantly. Allow mixture to boil for 1 minute, stirring continuously. Add to fruit mixture and stir for 3 minutes.

Fill all containers to within ½" of tops. Wipe off top edges of containers and cover with lids. Let stand at room temperature 24 hours. Marmalade is now ready to use. Store in refrigerator up to 3 weeks or freeze up to one year.