I'm interested in who introduced (and/or when) the standard liturgical formula for bruchas, that is, that they start with
- (a) 'ברוך אתא ה
- (b) that, followed by אלוקנו מלך העלום
- (c) in the case of positive commandments, those followed by ...אשר קדשנו במצותיו וץונו
What I can figure out is that (a) dates back at least to anshei ha-k'nesset hag'dolah, because the Shmoneh Esrey early blessings date back at least that far, and (c) dates back at least to the time of the Gemorrah, because in Shabbos they give the words for the Hanukkah candle blessing.
But these might go further back; for all I know, Moshe was using (a) when he benched after meals.