  Stellar-mass primordial black holes (PBHs) from the early Universe can
directly contribute to the gravitational wave (GW) events observed by LIGO, but
can only comprise a subdominant component of the dark matter (DM). The primary
DM constituent will generically form massive halos around seeding stellar-mass
PBHs. We demonstrate that gravitational lensing of sources at cosmological
($\gtrsim$Gpc) distances can directly explore DM halo dresses engulfing PBHs,
challenging for lensing of local sources in the vicinity of Milky Way. Strong
lensing analysis of fast radio bursts detected by CHIME survey already starts
to probe parameter space of dressed stellar-mass PBHs, and upcoming searches
can efficiently explore dressed PBHs over $\sim 10-10^5 M_{\odot}$ mass-range
and provide a stringent test of the PBH scenario for the GW events. Our
findings establish a general test for a broad class of DM models with
stellar-mass PBHs, including those where QCD axions or WIMP-like particles
comprise predominant DM. The results open a new route for exploring dressed
PBHs with various types of lensing events at cosmological distances, such as
supernovae and caustic crossings.
