The ever-growing popularity of WLANs has lead to a numerous and highly diverse set of solutions for increasing the available link data rates. Amongst these solutions, channel bonding offers the possibility to use wider channels and increase the data rates by a factor of two, four, or eight. The issue of properly selecting the channels and their width remains a complex problem. In this paper, we present a fast, scalable, and fully graph-centric strategy for choosing a channel width and assignment for the APs of an IEEE 802.11-based WLAN. It typically outperforms strategies consisting of selecting the channel width regardless of the WLAN topology by 15% in fairness and 20% in throughput.