Put in a large pot of boiling water and when the water returns to the boil, let boil for 3 minutes.
Remove from pot with slotted spoon.
Pack into ¼ litre (½ US pint) or ½ litre (1 US pint) jars.
Leave 3 cm (1 inch) headspace.
Add 1 ½ teaspoons vinegar to each ¼ litre (½ US pint) jar; 1 tablespoon vinegar to each ½ litre (1 US pint) jar.
Top up each jar with clean boiling water (such as from a kettle, for instance), maintaining headspace of 3 cm (1 inch.)
Debubble; adjust headspace.
Wipe jar rims.
Put lids on.
Processing pressure: 10 lbs (69 kPa) weighted gauge, 11 lbs (76 kpa) dial gauge (adjust pressure for your altitude when over 300 metres / 1000 feet)
Processing time: either size jar 35 minutes.
Notes
Do not do larger jars.It is one thing as a cook to brave prepping one or two jalapenos with bare hands; it is a different thing altogether to prepare them in industrial quantities. Wear gloves, or your hands will go dry and burn for hours on end, even with mild Jalapeno peppers. (Sweet peppers are fine.)The seeds are where the heat are; you can leave some in, if you wish.