Ennis’s [1] restaurant of note is the 
Continental Divide (47 Geyser St., 406/682-7600, 5:30–10 p.m. daily May–Oct., $26–36, reservations recommended), where creative, sophisticated bistro-style meals are served in a setting that’s not too intimidating to be a real treat. It’s in a seemingly unlikely location north of town near Ennis RV Village; however, views are great from the outside dining area.
Local ranchers hang out at the Silver Dollar Saloon (131 E. Main St., 406/682-7320) and the Longbranch Saloon (125 E. Main St., 406/682-7370, 10 a.m.–2 a.m. daily). Both places also have steak restaurants; the one at the Longbranch is better.
At Cowboy Heaven (319 E. Main St., 406/ 682-7773) you can swill espresso, smoothies, or milkshakes and eat tasty baked goods.
Down the road in Cameron, spend a spirited Saturday night at the Blue Moon Saloon (406/682-4612). Still farther south, in the West Fork area, the Grizzly Bar & Grill (406/682-7118, 11 a.m.–9 p.m. daily, $12–27) cooks its excellent steaks in an open-pit grill.
Links:
[1] http://www.moon.com/destinations/montana/the-missouri-headwaters-and-south-central-montana/three-forks-and-the-madison-river-valley/ennis