  We study tunneling spectroscopy between a normal metal and underdoped cuprate
superconductor modeled by a phenomenological theory in which the pseudogap is a
precursor to the undoped Mott insulator. In the transparent tunneling limit,
the spectra show a small energy gap associated with Andreev reflection. In the
Giaever limit, the spectra show a large energy gap associated with single
particle tunneling. Our theory semi-quantitatively describes the two gap
behavior observed in tunneling experiments.
