Which brewing method involves repeatedly cycling boiling water through coffee grounds?

The brewing method that involves repeatedly cycling boiling water through coffee grounds is percolation. In this technique, hot water is forced through the coffee grounds and then returned to a reservoir, allowing for continuous extraction. This cycling process helps to create a robust flavor profile by ensuring the coffee grounds are extracted multiple times, leading to higher caffeine and flavor extraction compared to a single-pass method.

In contrast, the French press immerses coffee grounds in hot water for a short period before pressing them down, which does not involve the repetitive cycling of water. Drip brew, while it involves brewed water passing through coffee grounds, typically does so in a single pass as the water drips through a filter and into a carafe. Cold brew, on the other hand, involves steeping coffee grounds in cold or room-temperature water for an extended period, with no boiling water or cycling mechanism used at all.