Tahoe died after tune up. Whats wrong?

[Brewcity]

Hey guys...just got done with new plugs, wires, and valve cover gaskets today. She fired right up, and I drove her around the block to see how it idled and ran. It was about a 2 minute drive...got back to the driveway, and the Tahoe stalled. The battery light went on...so I just cranked her back on, and all seemed fine.
I checked under the hood...and all seemed fine and everything was bolted down tight.
What should I be looking at? Did I miss something? Why would this happen? It never stalled out before.
Thanks for the help with this. I appreciate it!