Premise: Breton sauce, (fr. "Sauce Bretonne") is a French compound sauce consisting of a velouté base with julienned onion, leeks, celery heart and mushrooms, mounted with butter and cream. It has been referred to as a brown version of "Sauce soubise" which has as its base a béchamel sauce.
Hypothesis: Breton sauce, (fr. "Sauce Bretonne") is a French compound sauce consisting of a velouté base with julienned onion, leeks, celery heart and mushrooms, mounted with butter and cream which most people would call a béchamel sauce.