The versatility of optical parametric amplifiers make them excellent sources for next-generation ultrashort strong-field physics experiments, however phase matching considerations limit the available bandwidth. We demonstrate supercontinuum amplification in a four-wave optical parametric amplifier by Kerr instability. Experimentally, we amplify spectra that span nearly an octave without spatial chirp, with two-cycle transform limited pulse duration. We also theoretically explore regimes that demonstrate single-cycle amplification in the near infrared.