Any move that doesn't allow black a safe check with the queen- so Kb2 or Kc4 should suffice. 1.Nxe1 will only draw . So....

1.Kb2 f1(Q)

And now white has the check from e5 followed by the protected capture at e1...

2.Qe5 Kf3 3.Qxe1 wins.