Thanks Testu, for sharing a great recipe. Though I made a mistake, the beverage was so delicious. It was taste of summer. (I forgot to adjust my grinder so dripping was very fast though.)
30 gr of coffee with 90 gr of water. (1:3), with 20 gr sugar. And a dash of lime. Chill the coffee to prevent too much co2 reaction with the coffee Pour 150ml of soda water Pour 45gr of the coffee mix