Remove the stems, seeds and ribs from the bell peppers, jalapeno peppers and serrano chiles and coarsely chop them. (Pro tip: Always wear rubber gloves when handling hot peppers. Otherwise there is an approximately 100% chance that you will go on to touch your eyes, or worse, and pain ensues.) Pop your chopped peppers into a food processor and pulse until finely chopped.
If you prefer it to look a little more ... Christmassy, feel free to sub out some of the red bell peppers for green, and likewise use green jalapenos for some of the red.
Put your chopped peppers into a large nonreactive pot, like stainless steel or enamel. Do not use aluminum. Have at the ready the apple cider vinegar, powdered pectin and sugar. (Note: Pectin may be readily available at your local grocery store or even many hardware stores. Otherwise, it can be ordered online from major retailers.)
Meanwhile, if you are planning to can your jelly, prepare 6 half-pint jars and lids. Wash all jars and lids thoroughly with soap and water, and rinse well. Fill your canner with enough water to cover the jars by at least 1 inch and bring to a simmer. Using a pair of canning tongs, lower the jars in gently, tilting them to fill with the hot water. In a small saucepan, keep some water warm but not boiling; place the lids in the water. Have an additional kettle of water on to boil.
Add the vinegar and pectin to your peppers, and put on medium-high heat. Bring to a full rolling boil that does not subside when stirred.
Add the sugar, and return to a full rolling boil. Cook for exactly 1 minute, stirring constantly. Remove from heat, and skim away any foam on the surface.
If you are not canning the jelly, simply ladle into clean containers, allow to cool, cover and refrigerate. Use within 3 months.
If you are canning, fill and close the jars. Using canning tongs, remove the jars from the canner, carefully pouring the water back into the canner. Set next to the jelly in the saucepan. Turn the heat under the canner to high. Use a ladle to pour the jelly into the jars through a canning funnel, leaving 1/2 inch of headspace at the top. Run a clean chopstick around the inside of the jar to dislodge any trapped air. Wipe the rims of the jars with a damp paper towel. Place the lids on, and screw on the rings until just finger-tight.
Using canning tongs, gently transfer the jars to the canner, taking care to keep them vertical. When all the jars are in the canner, there should be at least 1 inch of water covering them; if you need more, add water from the kettle until the jars are sufficiently covered. Bring the water to a full rolling boil; process for 10 minutes.
Using canning tongs, gently remove the jars from the canner and transfer them to a kitchen towel or cooling rack, again keeping them vertical. Do not set hot jars directly onto cool counter surfaces. Leave to cool, undisturbed, for at least 12 hours. If any of the jars do not seal when cool, reprocess using the method above, or refrigerate and use immediately.