Online zero waste cooking class from Silo
7 days free, full access. Every masterclass, 50,000+ recipes, 1,500+ chefs.
Turn vegetable scraps into treacle, pork trim into garum and buttermilk into ice cream with Douglas McMaster, founder of Silo in London.
- 8 lessons
- 37 min
- Zero waste
- Easy
Rated 4.8 ★ by 60.2K App Store users · App of the Day in 120+ countries
What you'll learn
8 lessons · 37 min total
Introduction FREE
#1 Introduction to Zero-Waste FREE
#2 Vegetable Scraps Treacle FREE
#3 Miso Quaver with Vegetable Treacle FREE
#4 Roasted Pork Garum 
#5 Allium Top Oil 
#6 Grilled Onion with Pork Garum & Allium Oil 
#7 Shoyu Garumel 
#8 Buttermilk Ice Cream Sandwich
At the end of this course you will be able to:
Reduce strained vegetable scraps with 5% sugar to 107°C for a treacle thick enough to glaze.
Steam a miso and tapioca sheet, dry it at 57°C, then fry it at 180°C until it puffs.
Blend allium tops with 1.5 times their weight in oil to 64°C, then sieve straight onto ice.
Season a grilled onion by weight: 5% pork garum and 8% allium oil.
About this class
This online zero waste cooking class teaches the closed loop behind Silo through three dishes. Lesson #1 explains the system: direct trade, whole-food cooking and composting. Vegetable scraps are boiled, pressed and reduced to 107°C for a treacle that glazes the miso quaver, Silo’s puffed signature snack.
Koji drives the rest. Roasted pork trim, koji and 12% salt ferment into garum, which seasons a grilled onion with an oil made from allium tops. A garumel of caramel and bread shoyu follows, and buttermilk left from butter-making becomes an ice cream between bran wafers.
- Lessons
- 8
- Video
- 37 min HD
- Recipes
- 7
- Level
- Easy
- Audio
- English (VO)
- Subtitles
- English, French, German, Spanish, Italian
“Whether it’s bran, carrot skins, or buttermilk, we can show that these byproducts can be as exquisite as the primary products.”
Douglas McMaster · Lesson #8
PROTurn scraps into your best ingredients.
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MEET YOUR INSTRUCTOR
Douglas McMaster
Chef and founder, Silo, London
- Founder of SiloZero-waste restaurant, now in London.
- 50 BestNamed among chefs shaping the future of food.
Douglas McMaster is a British chef who left school to cook and went on to work at St. John, The Fat Duck and Noma. Meeting the designer Joost Bakker in Australia turned him to zero-waste cooking, first with a pop-up café in Sydney, then a restaurant in Melbourne.
At 26 he founded Silo in Brighton, now in London, and he runs the Zero Waste Cooking School. In this class he shows the system behind Silo, where, he says, composting fell from 10 to 15% of incoming food to about 1%.
Onion seasoning by weight
Example values. The allium oil in lesson #5 is one part allium tops to 1.5 parts oil.
Key concepts
Zero waste
A set of principles aimed at preventing waste so that resources are reused. Taught in lesson #1. (Wikipedia)
Miso
A Japanese seasoning made by fermenting soybeans with salt and koji. Taught in lesson #3, made here with spent beer grain. (Wikipedia)
Koji
Aspergillus oryzae, a mould used in East Asia to ferment foods. Taught in lesson #4. (Wikipedia)
Buttermilk
The liquid left behind after churning butter out of cream. Taught in lesson #8. (Wikipedia)
Frequently Asked Questions
Can I watch it for free first?
Yes. The introduction and lessons #1 to #3 are free to watch, no card required. To watch all 8 lessons with Douglas, start a Gronda PRO trial. Cancel before it ends and you pay nothing.
Do I need a fermentation chamber?
No. In lesson #4 the minced pork, koji, dashi (or water) and salt go into a jar or container to ferment for about three months, and the recipe notes that a hot cupboard speeds it up. The finished garum is not made on camera.
What level is it, and what language?
Easy level. Douglas teaches in English, with subtitles in English, French, German, Spanish and Italian.
Do I get the recipes?
Yes. Lessons #2 to #8 come with their ingredient list and written notes, available in the Gronda app or on gronda.com.
Can I watch on my phone?
Yes, in the Gronda app on iPhone and Android, or in the browser at gronda.com.
Can I cancel my membership anytime?
Yes. App Store or Google Play: in your phone’s subscription settings. gronda.com: in your account settings. No fees, no calls.
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