I will discuss a novel strategy to test lepton flavour universality (LFU) in top decays, applicable to top pair production at colliders. This proposal exploits information in kinematic distributions and mostly hinges on data-driven techniques. Based on simplified models accommodating recent hints of LFU violation in charged current B meson decays, I will show that existing LHC measurements already provide non-trivial information on the flavour structure and the mass scale of such new physics (NP). I also project that the measurements of LFU in top decays at the high-luminosity LHC could reach a precision at the percent level or below, improving the sensitivity to LFU violating NP in the top sector by more than an order of magnitude compared to existing approaches.