purim torah in jest - Is Cholent DeOraitha or DeRabbanan?

As definitively proven by an 'Am HaAretz Gamur MiDeOraitha (a title of high distinction if ever there was one), eating Cholent on Shabbath is required. Every week. Without exception.

But is this absolute requirement, with which no one dissents, based on a biblical commandment, or rabbinic enactment?

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