Almost everyone has been told the heat in a chilli lives in the seeds. It does not. Capsaicin is produced in the white spongy pith that the seeds are attached to, called the placenta, and the seeds only taste hot because they have been sitting against it.
That distinction is the whole point of learning to cut a jalapeño properly. If you know where the heat actually is, you can decide how hot the dish will be while you are prepping rather than finding out at the table.
This guide covers the three cuts you actually need, how to dial the heat up or down, and the part that catches people out hours later: capsaicin does not wash off with water.
What You'll Need
- A small sharp knife: A paring knife or a small chef's knife. Jalapeños are small and firm with a waxy skin, and a blunt blade skids off that skin rather than biting into it.
- Disposable gloves, if you are doing more than one or two: Not squeamishness. Capsaicin binds to skin and stays there through several hand washes, and it transfers to whatever you touch next. Eyes and contact lenses are the usual casualties.
- A non-porous prep surface: Capsaicin soaks into a wooden board and shows up in the next thing you cut on it. A ROO Mat gives you a non-porous silicone surface that rinses clean, and its pouch takes the stems, pith, and seeds without you handling them again.
How to Cut a Jalapeño, Step by Step
Wash and dry the peppers, then cut off the stem
Slice off the top quarter-inch including the stem and the shoulder it sits on. Leave the rest of the pepper intact for now. Dry peppers are much easier to hold than damp ones.
For rings, just slice across
Lay the pepper on its side and cut crosswise into rings about an eighth of an inch thick. Rings keep the pith and seeds in, so this is the hottest way to serve a jalapeño. It is what you want for nachos, pickling, or anything on top of a taco.
For dice, halve it lengthwise and scrape first
Stand the pepper on its cut top, slice down through the middle, and open it into two halves. Run the tip of a spoon or the back of your knife down each half to scrape out the white pith and the seeds attached to it. Then lay the halves skin-side down, slice into thin strips lengthwise, turn ninety degrees, and dice.
Decide the heat while you scrape
This is the control you have. Remove all the pith for mild, leave some of the ribs for medium, leave everything in for full heat. Two jalapeños from the same plant can differ noticeably, so taste a sliver of flesh before you commit if the dish depends on it.
For poppers, halve it and leave the shell whole
Cut lengthwise from just below the stem to the tip, keeping both halves intact, then scrape the pith and seeds out of each boat. You want a clean hollow shell that holds filling without splitting.
Clean up properly, with soap or oil
Capsaicin is not water soluble, so a rinse under the tap spreads it rather than removing it. Wash your hands with dish soap and warm water, twice. If they are already burning, rub them with a little cooking oil first to dissolve the capsaicin, then wash with soap. Milk works on the same principle if it is your mouth.
Photo by Los Muertos Crew on Pexels
Upgrade Your Prep: Get the ROO Bundle
ROO is a silicone mat that sits under your cutting board. It grips smooth countertops so the board never slides, and its built-in 7-cup pouch catches peels and trimmings as you cut. The Bundle includes the mat, a rubberwood board, and a reusable storage bag. $54.99.
Shop the ROO Bundle →Common Mistakes to Avoid
The seeds are not where the heat is made. Taking them out while leaving the white pith behind barely changes anything. Scrape the pith, and the seeds come away with it anyway.
Capsaicin lingers on skin for hours and transfers readily. Eyes, nose, and contact lenses are where people discover this. If you handle more than a couple of peppers, wear gloves.
Capsaicin is oil-soluble, not water-soluble. Plain water moves it around. Dish soap breaks it down, and rubbing oil on first then washing with soap works even better.
Wood is porous and absorbs the oil. The next thing you slice on that board picks up heat, which is a nasty surprise in a fruit salad. Use a non-porous surface, or keep one board for chillies.
Upgrade Your Prep Workflow: The ROO Bundle
Chillies are the strongest argument there is for a non-porous prep surface. Capsaicin is an oil, wood absorbs oil into its grain, and the board that seemed fine after a rinse turns up in your next fruit salad. The ROO Mat is silicone, so nothing soaks in and it goes straight in the dishwasher, it grips the counter while you make fine cuts on a small round pepper, and its built-in 7-cup pouch takes the stems, pith, and seeds so you are not scooping capsaicin off the board with your hands. The Bundle pairs it with a 13.75" x 9.75" rubberwood board and a reusable storage bag.
Upgrade Your Prep Workflow: Get the ROO Bundle
Nothing soaks in, so the heat does not follow you to the next ingredient.
Check out the ROO Bundle →Related Reading
- How to Chop and Dice a Bell Pepper
- How to Keep Guacamole From Browning
- How to Clean a Wooden Cutting Board
Frequently Asked Questions
Do you take the seeds out of a jalapeño?
Only if you want to, and it makes less difference than people expect. The heat is in the white pith the seeds attach to. Scrape the pith out and the seeds come with it, which is the part that actually reduces the heat.
Are you supposed to wear gloves when cutting jalapeños?
For one or two, most people manage without. For a batch, yes. Capsaicin binds to skin and survives several washes, and the delayed burn on your fingertips hours later is a common and avoidable experience.
How do you cut a jalapeño without the heat?
Halve it lengthwise, scrape out all the white pith and seeds with a spoon, and rinse the inside. You are left with the flesh, which carries the grassy pepper flavour and very little capsaicin.
How do you stop your hands burning after cutting chillies?
Rub a little cooking oil into your hands to dissolve the capsaicin, then wash with dish soap and warm water. Repeat if needed. Water alone will not do it, because capsaicin is not water-soluble.
Why are some jalapeños hotter than others?
Growing conditions and age. Peppers stressed by heat or low water produce more capsaicin, and older peppers are hotter. The fine white lines that show up on some jalapeños, sometimes called corking, generally indicate a more mature and hotter pepper.
Stem off, then either slice into rings for full heat or halve and scrape the pith for control. The pith is the heat, the seeds are just along for the ride, and dish soap is what actually gets capsaicin off your hands.