I think he wants it the other way, i.e. from BCS to derive GL theory.I think that you are asking for the impossible unless you consider quantum field theory simple. The following is an historical overview of the process of developing the BCS microscopic theory from the Landau-Ginzberg free energy model by its original author, Lev Gor'kov: Gor'kov paper (LG to BCS)
Quantum field theory, or second quantization, is simple in my view. But the way how it is used, for instance, in the book by Abrikosov, Gorkov and Dzyaloshinskii is not simple. On the other hand, the book by Mattuck is much simpler. An even simpler book on QFT is the one by Lancaster and Blundell (QFT for the Gifted Amateur), which in fact does give a rough simple idea of how to get GL from BCS and something more complete on that level would be very desirable. I hope it helps to get a picture of what do I mean by "simple".I think that you are asking for the impossible unless you consider quantum field theory simple.
It appears to be available on arxiv.A. Schmitt, Introduction to Superfluidity, Springer 2015