Exquisite food, great service, comfortable atmosphere. I've been here many times and it has never disappointed. This is a true "brunch", with bacon, omelets to order, eggs benedict, bagels with salmon, and juicy prime rib, roast leg of lamb, oysters on the half shell, vegetables...well you can read the menu on-line. All I can say is that everything is delicious.
Oh, and the desserts and baked goods are all made in-house. Don't miss the creme brullee! The coffee is hot and strong; the service is attentive; the atmosphere is rustic. Even though there are table linens and real silver, there's nothing stiff or formal about the Greenbriar--this *is* Boulder, after all. You can pretty much wear anything, as long as you're wearing something:)
The Greenbriar is also a great place to go for dinner on that special occasion, but I'm rather addicted to the brunch. It is a bit on the pricey side--$28.00, but well worth it for what you get. You can pay less elsewhere if you want bland, steam-table fare.
The Greenbriar is out in the country, between Boulder and Lyons, and definitely worth the drive from just about anywhere. I have friends who come up from Denver just for the brunch--it's that good. In summer they have outdoor seating as well.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.