Barb Schaller's* Mango-Strawberry Jam with Kiwifruit
*That's the important part of the recipe title. :-)
rec.food.cooking/Melba's Jammin' (1998/2000)

2 cups diced mango (1 lb)
1 3/4 cups mashed strawberries
3/4 cup diced kiwi
1/4 cup lemon juice
1 tsp citric acid
7 1/2 cups sugar
2 pouches Certo

Follow Certo instructions for making cooked Strawberry Jam, using the amounts of fruit and pectin above; i.e., combine the fruits, acids, and sugar in a large heavy kettle or saucepot and bring to boil. Then stir in the Certo, return to hard boil and boil one minute before jarring and processing properly in a boiling water bath as any good Jam Queen (or wannabe) would. (I use a 6-quart stainless steel saucepot -- it's my pressure cooker pan when it's not cooking jam. I think the citric acid is important. I bought my last batch at Sweet Celebrations (candy/cake decorating place). Don't confuse it with ascorbic acid. Citric acid is what puts the pucker in fruit-flavored lollipops.

Trick to a lot of jams is to use 3/4 ripe fruit, 1/4 slightly underripe. The trick to this one, IMNSHO, is to find all the fruits at the proper ripeness at the same time! I like my mangoes on the firm ripe side. Smash the strawberries with a potato masher, not the food processor. I made some yesterday and it's looking good!

Source: Made it up for 1996 State Fair. Best stuff I made all summer; it didnšt win a thing at the Fair. Humbug! But it did win First Place in 1997!!