Why in this sentence the stem of the verb is used instead of the verb 炒める itself?
まず、玉葱を炒め、次に肉を入れて下さい。
Why in this sentence the stem of the verb is used instead of the verb 炒める itself?
まず、玉葱を炒め、次に肉を入れて下さい。
Most often in literary or written formats, you will see the 'verb stem' used in this way as a less 'colloquial' alternative to the て-form. So your example can also be rendered as follows:
まず、玉葱を炒めて、次に肉を入れて下さい。
See also this thesis entitled "On Japanese Coordinate Structures: An Investigation of Structural Differences Between the -te and the i-form", if you are interested to read a rather more detailed treatment on the subject!
Hope that helps!