I discuss our newly constructed Λ hyperon EoS for core-collapse super- nova simulations and neutron star mergers. This is the first supernova EoS involving Λ hyperons which is compatible with the recently measured 2 M⊙ neutron star. I describe the role of strange baryon matter on supernova sim- ulations in a general relativistic one dimensional code using our Λ hyperon EoS and neutrino signal. In this context, I also discuss the metastability of the protoneutron star and its connection to the fate of SN1987A.