In a medium saucepan
whisk together flour, sugar, lemon juice and water until well blended on a low-medium heat. (See above note about the amount of water). Add all but 1 cup of the fresh or frozen fruit, reserving the rest. Stir occasionally until it comes to a gentle boil (about 10 minutes or so) and is the desired consistency. Add another 1/2 cup or so more fruit right toward the end of cooking, so there will be some chunky pieces of fruit that aren't cooked all the way down.