Session 16
Dialing in & troubleshooting
Session 16 · Block E — Brewing & Extraction

Dialing in
& troubleshooting

The skill that changes your daily cup: a repeatable method for turning a mediocre brew into a good one, using the compass and one variable at a time.

Duration
40 min · 30 learn / 10 review
You’ll need
Brewer, grinder, scale, a coffee
Objective
Fix any cup systematically
Reading · 1 of 2

The compass, applied

Every dial-in comes back to one question: is the cup sour (under-extracted) or bitter/harsh (over-extracted)? Sour → grind finer. Bitter → grind coarser. Balanced → stop. Almost everything else is refinement.

The subtle case

A cup can be both sour and bitter at once — the signature of uneven extraction, usually a poor grinder or (in pour-over) channeling, or (in espresso) bad puck prep. When you can’t dial it out with grind, the problem is evenness, not amount.

Reading · 2 of 2

A repeatable method

  1. Set a baseline recipe

    Pick a starting ratio (e.g. 1:16 filter) and a middle grind. Write it down. Dialing in requires a fixed starting point.

  2. Change one variable

    Adjust grind only, in clear steps. Never move two things at once or you won’t know what worked.

  3. Taste and name the fault

    Sour or bitter? Move grind accordingly and re-brew.

  4. Record the winner

    When it’s balanced, write the recipe down. Reproducibility is the whole point (Session 20).

Do this now · ~10 min

Run a full dial-in

  1. Brew your baseline

    Note ratio, grind, taste.

  2. Apply the compass twice

    Two correction rounds, grind only, tasting each.

  3. Log the recipe

    Save the balanced recipe so tomorrow’s cup starts from a win, not a guess.

Check yourself

Questions

Drill

Flashcards

Prompt
tap to flip
The 10-minute review

Lock it in

From memory:

  1. Sour cup — what do you change?
  2. Bitter cup — what do you change?
  3. Why change one variable at a time?
  4. What does "sour AND bitter at once" mean?
  5. What’s the single best home upgrade?
Session 17 · Block E — Brewing & Extraction

Pour-over &
filter technique

The clean, articulate side of coffee, and the manual craft most rewarding to learn. Bloom, pour, bed — the moves that make filter reproducible.

Duration
40 min · 30 learn / 10 review
You’ll need
A pour-over device, or press
Objective
Execute a clean, even filter brew
Reading · 1 of 1

How filter works, and how to do it well

Filter is percolation — water passing through a bed of grounds — or immersion. Click through the technique that makes it even:

Do this now · ~10 min

Brew a deliberate pour-over

  1. Bloom

    Wet the grounds with ~2x their weight in water; wait 30–45 s and watch them swell.

  2. Pour in stages

    Add water in steady, controlled pours, keeping the bed even; avoid gouging the center.

  3. Read the bed

    A flat, even spent bed = even extraction; a crater or slope = channeling. Adjust your pour next time.

  4. Taste against the compass

    Sour → grind finer; bitter → coarser. Same compass, now with pour control layered on.

Check yourself

Questions

Drill

Flashcards

Prompt
tap to flip
The 10-minute review

Lock it in

From memory:

  1. How does pour-over extract?
  2. What is the bloom for?
  3. What is channeling and how do you spot it?
  4. Contrast French press with paper pour-over.
  5. Why is immersion more forgiving?
Session 18 · Block E — Brewing & Extraction

Espresso
technique

The unforgiving one — and the reason brewing earned its expanded weight. Pressure, a fine puck, and seconds that magnify every error into the cup.

Duration
40 min · 30 learn / 10 review
You’ll need
An espresso machine & grinder
Objective
Understand the shot & its failure modes
Reading · 1 of 1

What makes espresso hard

Espresso is a different discipline: ~9 bar of pressure through a fine, compacted puck in under 30 seconds. Click through what that demands:

If you don’t have a machine

You still need this session: it’s why café espresso varies so much, why baristas obsess over grind and prep, and why a moka pot or AeroPress "espresso-style" brew isn’t the same drink. Understanding the shot makes you a sharper judge even if you never pull one.

Do this now · ~10 min

Dial a shot (or diagnose one)

  1. Weigh in and out

    Start ~18 g in, aim ~36 g out in ~25–30 s. Weigh both — espresso is dialed by weight and time.

  2. Read the flow

    Gushing and fast → sour, under-extracted → grind finer. Dripping and slow → bitter, over-extracted → grind coarser.

  3. Check puck prep

    Simultaneously sour and bitter, or a squirting shot? Suspect uneven distribution/tamp — channeling, not grind.

Check yourself

Questions

Drill

Flashcards

Prompt
tap to flip
The 10-minute review

Lock it in

From memory:

  1. Define espresso by pressure, grind, time.
  2. Give a common dose/ratio/time starting point.
  3. Why does puck prep matter?
  4. Fast gushing shot — what and why?
  5. Why does espresso deserve its own session?