Female or Male, Leading or Supporting, a performance remains a performance!
The title is self-explanatory. Descriptions are included in the spoiler-free notes section, suggestions are very welcome (particularly post-2010), and additions are based on purely personal preference. This list went through months of thought and rewatches, but you always forget about including "that" performance.
The omission of a particular performance might not correlate with the popular consensus and viceversa, but please feel free to comment even if I have seen the film and not included a performance. I MIGHT be convinced....