First time post.

I have a 2007 Cooper S that I've owned for about a year. Just a few days ago I took it in for the recall work on the auxiliary water pump. Then today while driving my daughter to school a new warning light came on and my brake pedal went totally spongy and then all the way to the floor leaving minimal stopping power. Got my daughter to school (safely) and checked the brake fluid reservoir - half way between max and min.

So I waited a few minutes, then started it up again and still brake pedal still to floor with brake and dsc warning lights on. Managed to get it to a dealer a few blocks away (different dealer did recall work) and by the time I finished checking in my car there was a puddle of brake fluid under the car and the reservoir was now empty.

Is there any way a tech could have done something or forgot to reconnect something during the recall work that would of caused this?

Nope, the clutch slave cylinder is nearby but you would loose the clutch way before the brakes if it was anything around there.
Where was the puddle from under the car?