Dim a 110 Light using 5v PWM with no ZC
If you search online you can find ready made dimmer control modules that can take in a PWM signal and control an AC powered light. The modules I saw take care of the necessary zero cross detection and phase control on the module.

Search for "PWM AC Voltage Dimmer 50/60Hz 80-240VAC"  at large online retailer to find this. 

As with anything AC mains connected, module or self built, use much care for safety and caution to avoid injury and property damage.