Banberry Jam

From Linda J.Amendt's Book "Blue Ribbon Preserves". The taste and color of this jam are delightful. Please don't duplicate the ingredients, or the jam may fail to set.

• Ready In: 1 hr 5 mins
• Yields: 7 half-pint jars

Ingredients

• 2 1⁄2 cups  ripe strawberries, hulled and crushed
• 1 3⁄4 cups  ripe bananas, peeled and mashed
• 2  tablespoons bottled lemon juice
• 7  cups sugar
• 1⁄2 teaspoon unsalted butter (optional)
• 1 (3 ounce) envelope  liquid pectin

Directions

1. In an 8-quart pan, combine the strawberries, bananas, lemon juice, sugar and butter.
2. Over medium-low heat, stirring constantly, heat the mixture until the sugar is completely dissolved.
3. Increase the heat to medium-high and bring the mixture to a full rolling boil, stirring constantly. Stir in the entire contents of the pectin pouch.
4. Return the mixture to a full rolling boil, stirring constantly.
5. Boil, stirring constantly for 1 minute.
6. Remove the pan from the heat.
7. Skim off any foam.
8. To prevent the jam from separating in the jars, allow the jam to cool 5 minutes before filling the jars. Gently stir the jam every minute or so to distribute the fruit.
9. Ladle the hot jam into hot jars, leaving 1/4-inch headspace.
10. Wipe the jar rims and threads with a clean, damp cloth.
11. Cover with hot lids and apply screw rings.
12. Process half pint jars in 200°F (93°C) water bath for 10 minutes, pint jars for 15 minutes.