As far as I know, the most accepted Posek around the entire non-Chassidic Ashkenazi world is the Mishna Berura (and of course the Rama). He wrote the sections to his commentary to the Code of Jewish Law:
- Mishna Berura - concise and easy to learn additional laws and customs to the Shulhan Aruch as well as explanations usually bringing earlier sages such as: Elya Raba, Magen Avraham, and Baer Hetev.
- Biur Halacha - a little more in depth than the Mishna Berura where he usually sources his opinions and says why he holds like does
- Shaar HaTziyun - the sources for his words
Do the Ashkenazim that follow the M"B follow the words of the Biur Halacha as well? Or does this Hashkafa differ by Minhag?