They are typically identified by a low, horseshoe-shaped mound of burnt and shattered stone, the debris left from repeatedly heating rocks in fire and plunging them into water-filled troughs to cook food or process other materials. The example uncovered at Lisronagh in County Tipperary adds a quiet layer of detail to that familiar picture, because the excavation there in 2002 caught the moment before the full explanation arrives, leaving several questions carefully open.

The burnt mound itself, measuring 7.8 metres east to west and 5.3 metres across, survived to a maximum height of only 0.2 metres, so much of the original structure had already been lost or dispersed. Two troughs had been cut directly into the subsoil; the first was roughly circular, about two metres in diameter and 0.47 metres deep, while the second was slightly larger and similarly shallow. Neither had been lined with timber planks or stone slabs, which is notable, since lining was a common feature of such installations. What both troughs did share were small oval stake-holes at their bases, positioned away from the edges and interpreted as the impressions left by a basket-style container used to hold meat during cooking. Several smaller pits, each around a metre across, were also found nearby, possibly used in the storage or preparation of food. To the east, an arc of post-holes suggested a simple, open-sided shelter for whoever was working at the site. A radiocarbon date of 1610 plus or minus 40 BC was obtained from charcoal in the lower fill of the second trough, placing activity here firmly in the Middle Bronze Age. One detail the excavation could not resolve was the absence of any hearth; the stones must have been heated somewhere nearby, but that location left no trace in the ground that was examined.