'openssl/evp.h' file not found OS x Mongodb

This solution worked for me. If you don't already have openssl then first run brew install openssl. Then run:

$ cd /usr/local/include 
$ ln -s ../opt/openssl/include/openssl .

Two things are required. The one suggested by @ierdna was what was required for me to work, but only after I performed the following

~$ brew install openssl
~$ brew info openssl

Do the exporting as told by brew

~$ export LDFLAGS="-L/usr/local/opt/openssl/lib"
~$ export CPPFLAGS="-I/usr/local/opt/openssl/include"

Then do what ierdna tells you..

~$ cd /usr/local/include
~$ ln -s ../opt/openssl/include/openssl .

It worked for me immediately