  We present photometric and spectroscopic observations of the nearby
($D\approx28$ Mpc) interacting supernova (SN) 2019esa, discovered within hours
of explosion and serendipitously observed by the Transiting Exoplanet Survey
Satellite (TESS). Early, high cadence light curves from both TESS and the DLT40
survey tightly constrain the time of explosion, and show a 30 day rise to
maximum light followed by a near constant linear decline in luminosity. Optical
spectroscopy over the first 40 days revealed a highly reddened object with
narrow Balmer emission lines seen in Type IIn supernovae. The slow rise to
maximum in the optical lightcurve combined with the lack of broad H$\alpha$
emission suggest the presence of very optically thick and close circumstellar
material (CSM) that quickly decelerated the supernova ejecta. This CSM was
likely created from a massive star progenitor with an $\dot{M}$ $\sim$ 0.3
M$_{\odot}$ yr$^{-1}$ lost in a previous eruptive episode 3--4 years before
eruption, similar to giant eruptions of luminous blue variable stars. At late
times, strong intermediate-width Ca II, Fe I, and Fe II lines are seen in the
optical spectra, identical to those seen in the superluminous interacting SN
2006gy. The strong CSM interaction masks the underlying explosion mechanism in
SN 2019esa, but the combination of the luminosity, strength of the H$\alpha$
lines, and mass loss rate of the progenitor all point to a core collapse
origin.
