Coffee Brewing Guide — Americano & Flat White

Americano

A double espresso lengthened with hot water — bold, clean, and full-bodied. The order of pour matters: espresso first preserves the crema layer on top.

Dose

18g

Yield

36g

Time

25–30s

Water

120–180ml

Cup

~220ml

Crema

Thin golden layer — sign of good extraction

Double Espresso

18g in → 36g out in 25–30 seconds (1:2 ratio)

Hot Water

120–180ml from Dual Boiler's hot water tap, ~92°C

Method — Step by Step

Heat Up

Power on the Dual Boiler and allow at least 8 minutes for both boilers to stabilise. Run a blank shot to warm the portafilter and group head.

Dual Boiler

Grind

Set the Grinder Pro to the espresso range (start around setting 12, adjust finer/coarser to taste). Grind 18g into the portafilter using the 58mm cradle.

Grinder Pro

Distribute & Tamp

Level the grounds evenly using a WDT tool or finger, then tamp with firm, level pressure. The surface should be smooth and flat.

Technique

Pull the Shot

Lock the portafilter in and press the 2-cup button. Watch the pressure gauge — the needle should sit in the espresso range. Target 36g out in 25–30 seconds.

Dual Boiler

Add Hot Water

Turn the Dual Boiler's hot water dial to open. Fill the cup with 120–180ml of hot water to your preferred strength, then close the dial.

Dual Boiler

Serve

The crema should float on top. Stir gently if you prefer an even blend, or leave layered for a visual presentation. Enjoy black, or add a splash of milk.

Tip

☕ Americano Tips

Water first or espresso first? Espresso first, then water, keeps a crema layer on top. Water first (a "Long Black") gives a bolder, more integrated flavour — try both.

Water ratio: Start with a 1:4 ratio (espresso to water) and adjust. Less water for a stronger, more intense cup; more for something lighter and longer.

Brew temperature: The Dual Boiler's PID control defaults to 93°C. For lighter roasts, try bumping up by 1–2°C for better extraction.

Flat White

A velvety double espresso with silky steamed milk and a thin layer of microfoam — no more than 0.5cm. The milk should have a glossy, wet-paint consistency perfect for latte art.

Dose

18g

Yield

36g

Time

25–30s

Milk

120ml

Temp

60–65°C

Microfoam

Ultra-thin layer, ~0.5cm — glossy and smooth like wet paint

Steamed Milk

~120ml whole milk, textured to 60–65°C — silky, not frothy

Double Espresso

18g in → 36g out — the foundation of the drink

Method — Step by Step

Heat Up

Power on the Dual Boiler and wait at least 8 minutes. Both the brew boiler and steam boiler need to be at temperature. Run a blank rinse shot.

Dual Boiler

Grind

Set the Grinder Pro to espresso range (start around setting 12). Grind 18g into the portafilter. Use the 58mm cradle for a clean fit.

Grinder Pro

Distribute & Tamp

Distribute grounds evenly and tamp firmly. A level puck is critical for even extraction — don't press at an angle.

Technique

Pull the Shot

Lock in and press 2-cup. Target 36g out in 25–30 seconds. The Dual Boiler lets you extract and steam simultaneously — start steaming during the shot.

Dual Boiler

Steam the Milk

Pour ~120ml cold whole milk into a jug. Purge the steam wand. Position the tip just below the surface — introduce air for 2–3 seconds (gentle "tss" sound), then submerge to create a whirlpool. Stop at 60–65°C.

Dual Boiler

Texture & Pour

Swirl the jug and tap once on the counter to pop any large bubbles. The milk should look glossy. Pour from a height to blend, then bring the jug close to the surface for latte art.

Technique

🥛 Milk Steaming Guide — The Key to a Flat White

Start cold: Always use fresh, cold milk straight from the fridge. Cold milk gives you more time to texture before hitting temperature.

Aeration phase (2–3 sec): Keep the steam tip just at the surface. You should hear a gentle paper-tearing "tss" sound. This introduces the tiny air bubbles that become microfoam.

Texturing phase: Submerge the tip deeper and angle to create a whirlpool vortex. This breaks large bubbles into the silky microfoam and heats evenly.

Temperature: Stop at 60–65°C. Milk is sweetest around 60°C. Above 70°C, proteins break down and the milk tastes scalded and flat.

The test: Perfectly steamed flat white milk should look like glossy wet paint — no visible bubbles. It pours in a smooth, fluid stream.

✨ Flat White Tips

Flat white vs. latte: A flat white is smaller (150–180ml total), has less microfoam (~0.5cm vs 1cm), and a stronger espresso-forward flavour.

Dual boiler advantage: Because both boilers run independently, you can pull your espresso and steam milk at the same time — the shot stays fresh.

Milk choice: Whole milk gives the best microfoam and sweetness. Oat "barista" editions also work well. Skim foams aggressively — use less aeration.

Side by Side

Both drinks start with an identical double espresso — the difference is what comes after.

Americano

Flat White

Base espresso

18g → 36g double

Added liquid

120–180ml hot water

~120ml steamed milk

Total volume

~220ml

~160ml

Texture

Clean, thin, like filter

Silky, velvety, creamy

Foam

Thin crema only

~0.5cm microfoam

Flavour

Bold, clean, espresso-forward

Smooth, sweet, balanced

Milk steaming

Not required

Essential — 60–65°C

Cup style

Tall mug

Small ceramic cup/bowl

Difficulty

Beginner friendly

Intermediate — milk skill

Troubleshooting

Shot runs too fast (<20s)

Grind finer on the Grinder Pro — turn the dial one or two clicks towards finer and try again.

Shot runs too slow (>35s)

Grind coarser. Also check you're not overdosing — stick to 18g for the double basket.

Sour / acidic espresso

Under-extracted. Grind finer, increase dose slightly, or raise the brew temperature by 1°C on the Dual Boiler's PID menu.

Bitter / harsh espresso

Over-extracted. Grind coarser, reduce shot time, or lower brew temperature slightly.

Milk has big bubbles

Too much air introduced. Shorten the aeration phase to just 1–2 seconds. Keep the tip barely below the surface, then submerge quickly.

Milk is flat / no foam

Not enough air. Make sure you hear the "tss" sound at the start. The tip needs to be right at the surface to draw in air before submerging.