Create extend wifi from Mac to iPhone, from ethernet

Situation: I use my mac's ethernet for internet, because my apartment doesn't have a working router. However, I need wifi for my iPhone. Wifi is available from other apartments in the same building, however it's a weak/slow network speed.

Question: Can I setup a wifi hotspot coming from my Mac, that is connected to the internet via ethernet? This hotspot would require a password, so only my iPhone can connect to it.

Models: mid-2012 Macbook Pro Retina. Updated to Yosemite 10.10.2. iPhone 5s, updated to current software available, I don't remember the number.

Research: I have researched this topic. Majority are out of date, or are about iPhone TO mac hotspot, rather than Mac TO iPhone. Or they discuss from wifi to wifi. Seems no one uses ethernet anymore. (Ethernet OP btw).

Thank you! Hope I provided enough information.