  There has been a recent surge of interest in UTe$_2$ due to its
unconventional magnetic field (H) reinforced spin-triplet superconducting
phases persisting at fields far above the simple Pauli limit for H $\parallel$
[010]. Magnetic fields in excess of 35 T then induce a field-polarized magnetic
state via a first-order-like phase transition. More controversially, for field
orientations close to H $\parallel$ [011] and above 40 T, electrical
resistivity measurements suggest that a further superconducting state may
exist. However, no Meissner effect or thermodynamic evidence exists to date for
this phase making it difficult to exclude a simple low-resistance metallic
state. In this paper, we describe a study using thermal, electrical, and
magnetic probes in magnetic fields of up to 55 T applied between the [010]
($b$) and [001] ($c$) directions. Our MHz conductivity data reveal the
field-induced state of low or vanishing electrical resistance; simultaneous
magnetocaloric effect measurements (i.e. changes in sample temperature due to
changing magnetic field), show the first definitive evidence for adiabaticity
and thermal behavior characteristic of bulk field-induced superconductivity.
