  Higgs boson self-interactions can be investigated via di-Higgs ($pp\to hh+X$)
production at the LHC. With a small ${\cal{O}}(30)$ fb Standard Model
production cross section, and a large $t\bar t$ background, this measurement
has been considered challenging, even at a luminosity-upgraded LHC. We
demonstrate that by using simple kinematic bounding variables, of the sort
already employed in existing LHC searches, the dominant $t\bar t$ background
can be largely eliminated. Simulations of the signal and the dominant
background demonstrate the prospect for measurement of the di-Higgs production
cross section at the 30% level using 3/ab of integrated luminosity at a
high-luminosity LHC. This corresponds to a Higgs self-coupling determination
with 60% accuracy in the $b\bar b \tau^+\tau^-$ mode, with potential for
further improvements from e.g. subjet technologies and from additional di-Higgs
decay channels.
