Feijoa Jelly - cooking recipe

Ingredients

4 cups finely diced feijoas
1 cup cider vinegar
5 cups white sugar
1 (1 3/4 ounce) package dry pectin
1/2 teaspoon butter

Preparation

Place the finely diced feijoa into a 6 quart stock pot. Add the vinegar, butter and pectin and stir to combine.
Bring the mixture to a full rolling boil on high heat, stirring constantly. Stir in the sugar quickly, return to a full rolling boil and boil for 1 minute, stirring constantly.
Skim foam off the top if necessary (you shouldn't need to if using the butter in the recipe) and quickly ladle the hot jelly into prepared hot jars leaving 1/8 inch headspace. Adjust two-piece caps.
Process 5 minutes in a boiling-water canner (adjust for altitude).