Food & DrinkThe BestieIntermediate
Dialing In Espresso, a free food & drink course on Tomo

Dialing In Espresso

Move beyond rigid 1:2 recipe templates and learn to diagnose extraction in real time. Master puck prep, decouple grind and yield, and adapt machine parameters to any roast.

Like Duolingo, but for Dialing In Espresso. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.

A short one: 11 levels across 2 sections, about 22 minutes end to end, roughly 4 days at five minutes a day. It moves through Diagnosing the Extraction Loop and Steering the Variables. It assumes you already know the basics.

11 bite-size levelsAbout 5 minutes each

Free forever · No credit card · iPhone & Android

Brewster the Badger, the guide who teaches the Dialing In Espresso course
Dialing In Espresso
with Brewster the Badger
11
Levels
2
Sections
5
Min/day
What you'll learn

Key ideas in Dialing In Espresso

  • High-solubility organic acids and fruity aromatics extract into the cup first.
  • Mid-extraction dissolves complex sugars that give espresso sweetness and body.
  • Heavy plant fibers and astringent bitter polyphenols wash out last.
  • Under-extraction leaves sharp, vegetal sourness because sugars never dissolved.
  • Over-extraction strips heavy astringents that coat the tongue like dry black tea.
  • A balanced pull pairs ripe acidity with dissolved sugars to soften the finish.
  • Cut-off should track target beverage yield weight rather than an arbitrary clock time.
  • Fast liquid output at target yield reveals inadequate puck flow resistance.
  • Grinding finer increases puck resistance to slow the flow without cutting yield short.
  • Uniformly coarse grinds cause high flow rate and rapid blonding from the first drop.
  • A sudden mid-shot speedup with pale streaks signals a fracture or hole in the puck.
  • Water erodes the path of least resistance, causing localized over-extraction.
  • The first cup captures high-concentration crema, intense sourness, and salty notes.
  • The middle cup collects caramel sweetness, balanced body, and mellow acidity.
  • The final cup yields thin, watery, and astringently bitter liquid.
  • Water rushes rapidly through low-density pockets, over-extracting bitter tannins there
Why not just Google it

You've tried the other tabs

Wikipedia

Thirty open tabs. Four facts you actually kept.

YouTube

You watched. You nodded. By Sunday it was gone.

ChatGPT

One answer, then back to scrolling.

Online courses

Eight weeks. You meant to finish. You didn't.

Tomo gives Dialing In Espresso the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.

Try a question

Here's what playing it feels like

A real question from this course. Take your best guess.

Tasting How Espresso Extracts

What starts dissolving into your espresso during the middle part of the extraction?

Get it right to open this lesson and 10 more in the app.

Course map

Where Dialing In Espresso takes you

  1. 1

    Diagnosing the Extraction Loop

    • Diagnosing Taste and Flow
    • Puck Mechanics and Channeling
  2. 2

    Steering the Variables

    • Decoupling Ratio from Grind
    • Adapting to Roast and Pressure

2 sections · 4 units · 11 levels. Built to play, not to enroll.

New

Tomo is in ChatGPT

Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.

Add Tomo to ChatGPT
How it's taught

You pick the voice

This course
The Bestie

Dialing In Espresso is taught in the The Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.

Keep going

More Food & Drink on Tomo

Start free

Start Dialing In Espresso today.

Download Tomo, search Dialing In Espresso, and play your first lesson in under a minute.