A bill requiring all receiving electoral votes to submit proof of eligibility as per Constitutional requirements, prior to Congressional certification, under penalty of disqualification, would suffice.
Why not do it now?
I'd support it, though I don't know if it'd be Constitutional since the electoral votes have already been cast. But regardless, someone should take the lead and try and get legislation passed to prevent future elections from having this issue.
As to legislation, again, one member -- does he sit on the relevant committee? Would a Democrat chairman of said committee bring a bill up for committee debate, pass it on to full debate in the House, should it pass, then get it through the Senate??
On all these BC threads, I have attempted to make the point that we are long past the "say so" method when it comes to certifying candidates meet the Constitutional requirements for federal office. If they cannot get proper procedural legislation passed in Congress, then the legislature of each state ought to pass something, at the very least, the party hierarchy ought to have some method whereby one's citizenship is verified, in the case of presidential nomination, that the candidate is indeed natural-born.