Combine the sugar, chopped bell pepper, finely chopped and drained plums, diced apple, ginger, jalapeño peppers, vinegar and butter in a large, heavy pot. Stir to combine.
Bring the mixture to a boil and boil for 10 minutes, stirring frequently. After it’s cooked for 10 minutes, take a spoonful and allow the mixture to cool a bit. Taste and add additional jalapeño if you want more heat.
Add the fresh lemon juice and pectin and return the mixture to a vigorous boil. Boil for 1 minute, stirring continuously.
Cover jars and allow to sit for 24 hours at room temperature if you’re going to refrigerate or freeze the jam. Setting will occur as the jam cools and sits. After 24 hours refrigerate or freeze.