Hint: You Won't Find it at the Large Coffee Chains
The best coffees are never from those large chains that deal in such huge volume.
For one thing, you need a very fresh roast - ideally, roasted on site. That just can't happen at a large chain. Secondly, they don't have the time to make each cup special - they are an assembly line, basically. The difference between a truly gourmet, fresh-roasted cup of coffee and a regular, everyday cup is significant.
If you are buying coffee for your home, taking home a pound of coffee roasted that very day can be amazing. Brew that with your favorite brewer and you will taste the difference. We like the French Press, and the Pourover method for brewing coffee.
Fresh-roasted Espresso can be amazing!
The national chains not only have older coffee, but it is roasted in large batches - so the roasting process itself might not be as good as what a local, artisanal roasteria can do.
When you brew, make smaller amounts - coffee is best in the first 20 minutes or so. Brewed coffee can last a little longer in a sealed container, such as a vacuum-walled hot bottle that you can use to take coffee to work.
We find the national chains convenient, and they have gone to great lengths to have a nice environment - so they can be good when going with several friends, where socializing (and wifi access) is the focus.
But if you want a seriously good, gourmet cup of coffee - find that local roasteria.