No, In & Out is not in Idaho yet, but it's coming!
Weinerschnitzel is heading this way also.
Most of your other favorites are here - Burger King, Chick-Fil-A, McDonald's, Wendy's, & others
Locally owned fast food restaurants include the Westside Drive-in (State St./Parkcenter Blvd, Boise),
A plethora of coffee houses are everywhere in the Treasure Valley.
My personal fave is probably Rembrandt's in Eagle - it's an old restored church and located in downtown. They also have a full menu for breakfast and lunch. I also enjoy Eagle River Coffee; their selection is primarily sweet items.
Bright Eyes in Meridian is a popular place and they serve wine and have fun events in the evenings. I attended a "Sip & Paint" party there. Treasure Valley Roasters is an interesting place to check out - they offer 20+ varieties of coffee you can sample for only $ . 25! They also have those same coffee beans for sale, either whole or roasted. There is a limited menu available to take out, or enjoy at one of their many inside tables. A small gift shop rounds out the business.
Your favorite national chains are here too - Dutch Bros and Starbucks have many outlets around the Valley. Starbucks is also in many of the Albertson's.
Many pizza places in the Treasure Valley. In no special order, Smoky Mountain Pizzeria, Idaho Pizza Company, Fying Pizzaria all have numerous locations throughout the area. Red Bench Pizza is in Eagle and Pizza Connection is here also. The only national chains I've seen are Domino's and Papa Murphy's.
A variety of excellent Italian restaurants are located through the TV. From fun, traditional fare at Louie's in Meridian to an elegant dinner house, Bella Aquila, on the Greenbelt in Eagle. Vincenzo's is a small trattoria style eatery on State St. in Meridian and Luciano's has a location in Boise and Caffe Luciano's is on the river in Garden City. Be sure to check out Caci in Eagle for terrific Sicilian specialties.
From great steaks at Chandler's and Ruth Chris, both in downtown Boise to Crave in Eagle and everywhere in between, there is excellent American fare to be had. The Brickyard and Barbacoa are both known for their excellent steaks. For seafood, it doesn't get much better than Lucky Finn's on Eagle Road in Meridian. Enjoy delicious hamburgers and salads at Bardenay's. Oak Barrel in Eagle is a favorite as is the Tavern at Eagle Island (suggest the turkey club) Your favorite chains are here also - the Cheesecake Factory, Sizzler, Red Lobster, Yard House and many more.
One of the pleasant surprises I discovered when I moved here, was the large Basque population. And, there are place to enjoy this delicious cuisine. Epi's in Meridian is well know for its food and so is the Basque Marketplace in downtown Boise. You'll also find Basque specialties at restaurants such as Bardenay's.
For Thai food, check out Sa-Wah-Dee in Meridian. Other options include Mai Thai and Thai Basil.
It's Bacquet's and Roghani's in Eagle for French food. And, try the gyros, salads, and paninis at Bosnia Express Box in Boise for a Mediterranean style meal.
There is a lot of Mexican restaurants in the Treasure Valley. You'll have to go out and sample until you find the one(s) that suit your palate the best.
Food trucks abound here in the Treasure Valley. From private events to specific locations to farmer's markets, you'll find these around most of the year. I had a yummy quesadilla from one at the Eagle Saturday Market last week and a delicious carnitas taco at Eagle Fun Days last month.