Marco Castillo
Karen Liu
Rafael Peña
Sofia Torres
James Thompson

Meet the Team

Pepper growers, a food scientist, a trained chef, and a heat enthusiast — the people behind every profile, comparison, and guide on this site.

5 writers · 200+ varieties covered · Every fact checked
Marco Castillo

Marco Castillo

Founder & Lead Writer
187 pepper profiles 2 guides
I grew my first habanero at 14 in my grandmother's backyard in Oaxaca. That single plant turned into a lifelong obsession. Twenty years later, I've grown over 200 varieties across three climate zones, tasted every pepper in this database (yes, including Pepper X), and built KnowThePepper because I was tired of seeing wrong SHU numbers and recycled content everywhere. I've volunteered with agricultural extension programs in Central America, judged at the ZestFest Hot Sauce Awards, and my superhot garden has been featured in Chile Pepper Magazine.
Has tasted 200+ pepper varieties Judges at ZestFest annually First habanero at age 14 Featured in Chile Pepper Magazine
Pepper cultivation Superhot varieties SHU testing Hot sauce making Agricultural extension
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Karen Liu

Karen Liu

Contributing Editor & Food Scientist
4 guides
I spent three years in a food chemistry lab studying capsaicinoid extraction before I realized I'd rather write about peppers than pipette them. I'm the one who fact-checks every SHU number on this site against published research — if it's not in a peer-reviewed paper or a USDA database, it doesn't go live. I have a Master's in Food Science from UC Davis and an unhealthy attachment to my HPLC calibration curves.
UC Davis Food Science MSc Published in JAFC Former spice company QA Can identify capsaicin by smell
Capsaicinoid chemistry HPLC analysis Scoville testing Food safety TRPV1 receptor biology
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Rafael Peña

Rafael Peña

Growing Guide Author & Master Gardener
1 guides
I'm a Master Gardener with 20 years of dirt under my fingernails. I run KnowThePepper's trial garden in central Texas, where we test whether growing advice actually works across different soils and climates. Before peppers, I spent a decade growing heirloom tomatoes commercially. Turns out peppers are harder, more rewarding, and far more addictive to collect.
Master Gardener certified (Texas A&M) 2000 sq ft trial garden 80+ varieties per season Former commercial tomato grower
Pepper cultivation Soil science Seed starting Organic pest control Climate adaptation
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Sofia Torres

Sofia Torres

Culinary Writer & Recipe Developer
15 pepper profiles
I'm a trained chef turned food writer who believes peppers are the most underused ingredient in American kitchens. I worked the line at two Michelin-starred restaurants in Mexico City before moving to the US, where I now develop recipes and write about how peppers actually behave in a pan — not just how they taste raw.
CIA trained Cooked at Pujol and Quintonil Bon Appétit bylines 30+ hot sauces on the shelf
Mexican cuisine Recipe development Pepper substitutions Mole sauces Culinary techniques
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James Thompson

James Thompson

Hot Sauce Reviewer & Comparison Editor
9 comparisons
I have reviewed over 500 hot sauces and eaten more superhot peppers than my doctor would approve of. I write the comparison articles on KnowThePepper because I genuinely believe the best way to understand a pepper is to taste it next to another one. Before this, I ran a hot sauce review blog for four years and competed in chile eating contests. I placed third at the Puckerbutt Reaper Eating Challenge in 2022. My tolerance is stupid high. My taste buds somehow still work.
500+ hot sauces reviewed Puckerbutt Challenge 3rd place 87 bottles on the shelf Ran HeatSeeker blog 4 years
Pepper comparisons Hot sauce reviews Heat tolerance Tasting methodology Chile competitions
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How We Work

Every SHU number is sourced
No number goes on the site without a reference to a published study, USDA database, or verified measurement.
Growing tips are field-tested
Our trial garden tests advice across multiple soil types and climates before it gets published.
Recipes are cooked, not guessed
Substitution ratios come from side-by-side cooking tests, not theoretical calculations.
Comparisons include firsthand tasting
Every head-to-head comparison includes raw, cooked, and sauce-form tasting notes.
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