Prepare your jars: Wash and sterilize 4 half-pint (8 oz) canning jars, lids, and bands. Keep jars hot until ready to fill. This is crucial for preventing breakage and ensuring a good seal.

Combine peppers and liquids: In a medium saucepan, combine the chopped red bell peppers, green bell peppers, minced jalapeño peppers, apple cider vinegar, and lemon juice. Bring the mixture to a boil over medium-high heat, then reduce heat and simmer for about 10 minutes, or until peppers are softened.

Blend the pepper mixture: Carefully transfer the softened pepper mixture to a blender or use an immersion blender. Blend until smooth. Return the pureed mixture to the saucepan.

Add sugar and pectin: Measure the sugar into a separate bowl and set aside. In the saucepan with the pepper puree, stir in the powdered fruit pectin until thoroughly combined. Bring the mixture to a rolling boil over high heat, stirring constantly.

Add sugar and boil: Once the mixture reaches a full rolling boil that cannot be stirred down, add the measured sugar all at once. Stir continuously and bring the mixture back to a full rolling boil. Boil hard for exactly 1 minute, stirring constantly.

Skim and jar: Remove the saucepan from the heat. Skim off any foam that has risen to the surface with a spoon. Carefully ladle the hot jelly into the prepared hot jars, leaving about 1/4 inch of headspace. Wipe the rims clean with a damp cloth.

Seal the jars: Place the lids on the jars and screw on the bands until fingertip tight. Process the jars in a boiling water bath for 10 minutes (adjusting for altitude if necessary).

Cool and store: Carefully remove the jars from the water bath and let them cool undisturbed on a towel-lined counter for 12-24 hours. You should hear the lids 'pop' as they seal. Check seals by pressing the center of the lid; if it doesn't flex, it's sealed. Store sealed jars in a cool, dark place for up to a year. Refrigerate any unsealed jars or once opened.