  Although spin is a fundamental quantum number, measuring spin transport in
traditional solid state systems is extremely challenging. This poses a major
obstacle to detecting interesting quantum states including certain spin
liquids. In this paper we propose a platform that not only allows for the
electrical measurement of spin transport, but in which a variety of exotic
quantum phases may be stabilized. Our proposal involves two moir\'e
superlattices, built from transition metal dichalcogenides (TMD) or graphene,
separated from one another by a thin insulating layer. The two Coulomb coupled
moir\'e layers, when suitably aligned, give rise to a layer pseudospin degree
of freedom. The transport of pseudospin can be accessed from purely electrical
measurements of counter-flow or Coulomb drag conductivity. Furthermore, these
platforms naturally realize Hubbard models on the triangular lattice with $N =
4\, {\rm or}\, 8$ flavors. The flavor degeneracy motivates a large-N
approximation from which we obtain the phase diagram of Mott insulators at
different electron fillings and correlation strengths. In addition to
conventional phases such as psuedospin superfluids and crystallized insulators,
exotic phases including chiral spin liquids and a $U(1)$ spinon Fermi surface
spin liquid are also found, all of which will show smoking gun electrical
signatures in this setup.
