  We present MAXI and NuSTAR observations of the Be X-ray binary, MAXI
J0655-013, in outburst. NuSTAR observed the source once early in the outburst,
when spectral analysis yields a bolometric (0.1--100 keV), unabsorbed source
luminosity of $L_{\mathrm{bol}}=5.6\times10^{36}\mathrm{erg\,s^{-1}}$, and a
second time 54 days later, by which time the luminosity dropped to
$L_{\mathrm{bol}}=4\times10^{34}\,\mathrm{erg\,s^{-1}}$ after first undergoing
a dramatic increase. Timing analysis of the NuSTAR data reveals a neutron star
spin period of $1129.09\pm0.04$ s during the first observation, which decreased
to $1085\pm1$ s by the time of the second observation, indicating spin-up due
to accretion throughout the outburst. Furthermore, during the first NuSTAR
observation, we observed quasiperiodic oscillations with centroid frequency
$\nu_0=89\pm1$ mHz, which exhibited a second harmonic feature. By combining the
MAXI and NuSTAR data with pulse period measurements reported by Fermi/GBM, we
are able to show that apparent flaring behavior in the MAXI light-curve is an
artifact introduced by uneven sampling of the pulse profile, which has a large
pulsed fraction. Finally, we estimate the magnetic field strength at the
neutron star surface via three independent methods, invoking a tentative
cyclotron resonance scattering feature at $44$ keV, QPO production at the inner
edge of the accretion disk, and spin-up via interaction of the neutron star
magnetic field with accreting material. Each of these result in a significantly
different value. We discuss the strengths and weaknesses of each method and
infer that MAXI J0655-013 is likely to have a high surface magnetic field
strength, $B_{s}>10^{13}$ G.
