There are lots of places to eat in Destin - you won't have to eat at Outback or the Bonefish Grill. I'm really more familiar with Fort Walton Beach although we did eat a couple of times over in Destin. But that was some time ago and restaurants do go in and out of business. It's more fun to do your own research - ask people who live there.
Unfortunately, all restaurants in the Destin area are touristy during the summer months. You will likely suffer some long wait times, but as long as you realize that ahead of time, it'll make things easier. You can also try to go to dinner earlier to beat the rush.
One of my favorite seafood restaurants in the area is Dewey Destin's Seafood Restaurant, especially the bayside location. They have very fresh local seafood cooked in very simple but delicious ways. And the view (right on the water) is great, especially during sunset.
Bijoux is another great restaurant that specializes in steaks and local seafood. Their menu is a bit high-end for the area, so keep that in mind. But the food is arguably the best in town. Absolutely amazing food.
Pompano Joe's used to be a favorite of ours, but their quality has dropped a bit over the years. The view is unbeatable though (right on the beach), so it's a great spot for lunch. If you like grouper, the fried grouper sandwich is, in my opinion, the best thing on the menu, and it hasn't changed in years.
Louis Louis and The Red Bar, both owned by the same company, are very popular with locals as well as tourists. The menu is short and simple, but always amazing and features some local seafood. The ambience is extremely lively and always a good time.
Another upscale place that has pretty good food and a very nice and relaxing atmosphere is Caliza Restaurant. It's located in Alys Beach, which is a bit of a drive from Destin, but it's absolutely gorgeous there. It feels like a small Mediterranean town and the architecture of the area (and the restaurant) will make you think you're in Greece. Do a Google search for "Alys Beach" and you'll see what I mean.
I would probably try to stay away from any of the restaurants in the Harborwalk Village area as they can be very touristy and the food is typically not the best. However, it's fun to walk around the area and grab a drink down there by the water.
And finally, you may want breakfast/brunch at some point during your trip. If so, you absolutely must eat at Donut Hole Bakery Cafe or Donut Hole (two different locations). Hands down the best breakfast/brunch food in town. Another option is Mama Clemenza's, but it's fairly small, so there's a good chance you'll be waiting in line.
Hope this helps! Enjoy your trip!
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