Short version: Use a reputable package mix, omit the usual “1/4 cup water” and replace it with finely chopped/processered peppers of choice or even a prepared salsa. Follow the directions on the box for mixing and baking.
Perhaps it was from listening to The Splendid Table on public radio once upon a time, but somewhere I’d heard that spicy and chocolate can and do go together. Eventually I became curious enough to try it beyond mildly cinnamon flavored prepared chocolates. The first experiment that I can recall was a success: Diced jalapenos & juice in place of the (1/4 cup) water in a brownie mix. I think I used a food processor to chop things finer. There was some heat, but there was flavor and the heat was not dominating – at least not to me. It might be just on the edge of tolerable to a ‘supertaster’ who is apt to prefer only limited heat to spiciness if any at all.
Next the same trick of use-in-place-of-water was done with habanero. More heat, but not crazy – to me. This got me really curious. Or adventurous. I saw a jar of ghost pepper salsa. Yep, third verse, same as the first. And oh sweet (and spicy!) success. This is where even some non-supertasters might have second thoughts about seconds.
Some years ago, ESR was hosting a Friends of ‘Armed and Dangerous' party at Penguicon and I decided to offer some brownies. I made four pans: 1. Plain as plain 2. Jalapeno 3. Habanero 4. Ghost Pepper Salsa. After the party the three spicy pans were kept for a hot sauce (and other things?) tasting. The plain brownies were returned with, “I don’t know why you bothered with these.” Well, I figured some people desire spiciness of zero, so that’s why I bothered. However, in the following years only a single pan of ghost pepper salsa brownies sufficed for the party.
A few months ago some dried Carolina Reaper peppers were pointed out at a local supermarket. Using a bit of vodka to aid flavor extraction, I soaked & chopped a few and made brownies. Mind, this is where the kitchen becomes something more of a lab and real precautions get taken: NO TOUCH! Anything that can’t be cleaned immediately (and twice) is disposable. The favorite mixing spoon is set aside and another used, just in case. Hands washed. And washed again. And again. I’ve sampled the batter – it’s just on the lower edge of my tolerance. And it’s a sneak attack. That first taste doesn’t seem like anything much, but give it a few seconds and the spiciness materializes assertively. I’ve sampled the brownies so made, and the baking and the fudgy chocolate does knock things down considerably. Mind, the overall spiciness remains, but instead of a hideously large spark of heat, there is a slow-burn that lingers considerably unless quenched with something lipid-rich such as whole milk or cream.
The pack of dried peppers was more than I would dare to use in a single pan of brownies, so I only used maybe a third of the pack. Yesterday I used another third. While I am not bothering with Penguicon this year, ESR is still going and still hosting the Friends of Armed and Dangerous party. So I made the usual ghost pepper salsa brownies. And a pan of Carolina Reaper brownies. Sunday the reapers were selected, added to about 1/4 cup of vodka and muddled. Monday, after the ghost pepper brownies were mixed, they got the chopper treatment and went into the second batch. Baked. Cooled. Sealed. Packaged. Labeled. Sent.
I fully expect the folks at ESR’s party to enjoy them – in moderation. They are potent. I brought the first pan to work with the label from the pepper package on the cover and some people evidently didn’t read and got a shock. One gal took a brownie home and her husband tried it before being warned. I am told the reaction was on the order of, “Who the hell does such a thing?!”
That last third of the package? Not sure. The store that had them seems to no longer carry them. I can understand as the appeal is limited. And evidently one person there chowed down on one (pepper)… and wound up drinking at least a pint of heavy cream to get through his shift after that.
 If the name includes ‘Country’ or ‘Smart’ and is cheaper than the obvious store brand, spend the extra few pennies and go with the store brand, at least. Betty Crocker, Duncan Hines, and Pillsbury are all perfectly acceptable – and interchangeable.
 ESR’s blog.
 Svedka – Saving the Belvedere for more subtle things.
 The Integral might be constant: The area under the curve is the same; but the curve changes shape.