Bresadola was an eminent Italian mycologist. He named this species after the equally eminent French mycologist Jean-Louis Émile Boudier. It has a mainly southern distribution in Britain, with no records north of Edinburgh on NBN Atlas. It enjoys rich soils in broadleaved woodland and is also found in nettle beds. This specimen was found in our greenhouse and will almost certainly have come here with bought compost.

References: 
Kibby, G. (2020). Mushrooms and Toadstools of Britain & Europe, Volume 2: Agarics, Part 1.
Knudsen, H. & Vesterholt, J. editors (2012 second edition). Funga Nordica, 2 volumes.
Overall, A. (2017). Fungi: Mushroom & Toadstools of parks, gardens, heaths and woodlands.