Tetsu Kasuya breaks brewing rules with a radical 10-pour coffee recipe

This guide breaks down how to replicate Kasuya's groundbreaking 10-pour Hario V60 method and compares it directly with a modern double-bloom approach.

The Equipment You Need

To construct these brews with precision, gather the following tools on your bar:

• Dripper: A standard cone-shaped dripper, such as the Hario V60 Neo or classic ceramic V60.
• Filter Papers: High-quality filters, like Cafec T-90 paper filters, to ensure optimal flow rate.
• Grinder: A premium manual or electric grinder capable of achieving extreme coarseness. Examples include the Comandante C40 or 1Zpresso Q2 heptagonal.
• Kettle: A goose-neck kettle for precise flow control.
• Scale and Timer: Essential for tracking the rapid intervals of the pours.
• Water: Heated to the designated brewing temperatures.

The Radical 10-Pour Method

This technique utilizes an incredibly coarse grind. The particles should resemble shattered wood chips rather than traditional sand-like coffee grounds.

1. Prepare the Dose: Weigh exactly 20 grams of light-to-medium roast coffee. Grind extremely coarsely. On a Comandante C40, aim for 40 to 45 clicks. On a 1Zpresso Q2, use approximately 82 clicks.
2. Heat Your Water: Set your kettle temperature to 95–96°C. You need hotter water to penetrate these massive, woody particles.
3. The First Bloom: Pour 30 grams of water to saturate the bed. Start your timer. Let this initial bloom rest for 30 seconds.
4. The 15-Second Pulse: Starting at the 30-second mark, pour exactly 30 grams of water. Repeat this 30-gram pour every 15 seconds.
5. Maintain the Pace: Continue the rapid pulses (at 0:45, 1:00, 1:15, 1:30, 1:45, 2:00, and 2:15) until you hit the final target of 300 grams at 2:30.
6. The Drawdown: Allow the water to drain completely. The total brew time should land between 3:00 and 3:30, targetting a 1.3% Total Dissolved Solids (TDS) concentration.

The Double-Bloom Counterpoint

For a comparative perspective, this alternative recipe uses a finer grind size and fewer pours at a lower temperature to highlight sweetness and structured acidity.

1. Prepare the Dose: Grind 20 grams of coffee significantly finer than the 10-pour recipe. Set your Comandante C40 to roughly 30 clicks (65 clicks on the 1Zpresso Q2).
2. Heat Your Water: Keep the water cooler, sitting at 90°C.
3. First Bloom: Pour 60 grams of water and let it rest for 30 seconds.
4. Second Bloom: At the 30-second mark, pour another 60 grams of water (reaching 120 grams total). Let it rest until the 1:00 mark.
5. The Final Push: Pour the remaining 180 grams of water in a single, controlled stream up to 300 grams. Use a slightly turbulent pouring style to intentionally move the coffee bed. Let it draw down completely by 2:15.

Troubleshooting the Extraction

Kasuya’s 10-pour method behaves differently than standard recipes. The water will initially rush through the massive gaps in the coarse grounds. By the fifth and sixth pours, however, the continuous agitation will eject micro-fines into the filter paper pores, slowing the drawdown down significantly.

If your total brew time finishes under 3 minutes, your grind is too coarse, which leads to a thin, sour, and under-extracted cup. If the brew stalls past 3:45, adjust your grinder slightly finer to reduce the generation of excessive shattering and fines.

Choosing Your Flavor Profile

While both methods can hit an identical 1.28% TDS, they yield vastly different tactile experiences. The 10-pour method delivers a loud, bright, and singular punch of acidity. The double-bloom recipe sacrifices that sharp edge for a more integrated sweetness, structural balance, and a syrupy, heavier mouthfeel.