SEI Teaching Question

Hello all,

long story short I have a Massachusetts teaching license from several years ago but next used (therefore still valid for 12 months of teaching). I'm interested in rejoining the profession but when looking for jobs they're all requiring a SEI certification. What is the best (by best i mean most painless) way to get it, if necessary. I heard that it's only required for renewing a professional license but since I see it everywhere on job postings I don't want exclude something that will prevent me from finding a job.

If I've understood correctly one could either but an SEI MTEL book, study and take the exam (though all books I see on amazon are poorly reviewed). Or can I just sit through one of those accredited online courses. Is that enough or do I still need an MTEL.

I appreciate any feedback.

Thanks!