2.3L Engine Coolant Reservoir Empty

Couple of things geezer; When you're driving the car, are you smelling a sweet smell inside the cabin with the heater running and fan at medium speed? You can actually taste it through the cabin air... Also, have you noticed and strange "fogging" on the lower inside windshield? (smears when you attempt to wipe it off).

If you answered yes to any of those 2 questions,you may possibly have a heater core or/inside hose connection leak.
Do a stone cold test: making sure the car has set overnight (you want the engine to be stone cold), open the hood and open the antifreeze reservoir ....rock the car back and forth a few times while keeping your eye on the reservoir and see if you notice any air bubbles coming up to the surface ( after the dealership topped the antifreeze,it should have been bled to remove excess trapped air in the system).

Using a Marker, put a small check mark on the plastic reservoir where the antifreeze level is, close the reservoir lid...and go for a drive, make sure the system has come up to full temps before you return back to your garage....while out driving, cycle through the heat settings; feet area only,middle, and top (defrost), and run the fan on high while doing this....this will help remove ANY remaining air in the closed loop system.
Head back and park the car and leave over night again,(obviously, on level ground) the following day, pop your hood and take a close level look at where the antifreeze is sitting compared to the marker you put on the day before...if the anti freeze level has gone down anywhere between 1/8" to a 1/4" it might be a blown head gasket (highly doubt it). report findings to your dealership if that is the case for further investigation.
Hope this help you out.

Well, they need to pressurize the system and see how much it drops/hr...( leak down test) if it is a blown head gasket drop would happen fairly quickly.The feed hoses would be clamped and tested first...that would clear weather it's a clamp/hose leak....if that passes they would usually pressurize the entire system, if the drop is rapid they would most likely look at the head gasket...a full visual inspection would first take place (under pressure)...first and foremost the water pump and connections...they may proceed with a green fluorescent dye test. They need to first rule out if the leak is external ( hoses, clamps, water pump, heater core and reservoir ) or internal (head gasket, water galley,)...it's hard to assess without proper diagnostics geezer.
Have you noticed any temp spikes on the temp gauge while you were driving? When I mentioned "steam" I also meant opening up the hood and smelling that sweet smell of antifreeze OR minimal steam rising to the front of the motor (left side).

Then I would first take a closer look at the water pump....after it has reached operation temps....sensor readouts are a bit less than actual "core temps"....core temps usually are closer at a 20 minute drive, where the engine block has reached max temps.....anti freeze thins out making it more "watery" at it's highest temps, this is when a leak (with the added closed system pressure) will produce or show a leak...I've seen water pumps that showed zero leaks,then shut engine down and you'll notice droplets coming out either by the bearing or the weep hole(s)...which is why a florescent green dye is your best bet at locating them...
These 2.3 eco boost engines are not that high compression to start with ( turbo application usually calls for lower compression) so short of a defective head gasket I cannot see how with normal driving, you would blow a head gasket.
Something tells me it could very well be your water pump.....what is your original mileage?
I also have seen perfectly good condition radiators spring a bottom leak, either due to a bad solder air pocket or a flying rock striking a rad core copper hose...I'd start with the most obvious and as a last resort, head gasket.
geezer... you could try and go over the engine bay compartment, with a good flash light, look at the water pump,look at the very bottom of your rad....run your hand over hoses,a close inspection of your thermostat housing...just make sure the car has been running for a while and everything is warm....when you shut it down,wait a few minutes before you examine the water pump.....everything is pretty tight (seals) so it will take a minute or two before liquid start to go through the seals,and at best, a sporadic odd drip.