@Bob Nelson 35Whelen
Need to go to breakfast here:
https://coffeecallbatonrouge.com
Cafe du Monde in New Orleans has the same fare and is far more famous, just a bit more expensive and smaller beignets. Coffee Call has been an institution in Baton Rouge since I was a wee lad, nowhere near the pedigree of CDM, but very good nonetheless.
Knowing your likely appetite, get a large order of beignet (pronounced "bn-YAY") "fingers." Also,
cafe au lait (half chicory coffee, half boiled milk). You get 1 free refill on the coffee.
Also, wear light-colored clothes as you will get powdered sugar on yourself. They have powdered sugar shakers on the tables, avail yourself of them.
There are several good breweries in an around Baton Rouge, I think you will enjoy any of them - Tin Roof, Parish Brewing, and Abita Springs are 3 of my faves from that part of the world. Doesn't matter which of their beers are available, you will like any of them. Abita Turbo Dog is my absolute favorite, a rich stout. If you like IPA, Abita's "Andy Gator" is somewhere around 9% alcohol. Very tasty, but don't say I didn't warn you.
If you guys go out for seafood, I'd totally recommend a seafood platter, it'll have nearly everything on it that S. Louisiana is famous for - fried catfish, oysters, shrimp, hush puppies, stuffed crab.
Sample a cup of red beans and rice, a historical Louisiana staple. For dessert, every place will have their own version of bread pudding, you have to order some. Sounds like it would be shit, but trust me. When you guys get back to Oz, I'll send you the recipe I use, very simple. but no dessert says "South Louisiana" the way bread pudding says it.
Time permitting on your drive over, you might stop in Henderson, Louisiana and enjoy Pat's of Henderson. Pat's has also been around for 50+ years, they're right on the Atchafalaya swamp. Of note, there are more alligators in Louisiana than nearly all the other states combined. There are 2 or 3 swamp tours within about 5 or 10 minutes' drive of Pat's. They're nowhere near your salties, but impressive beasts nonetheless. Only bad thing is it's October, so they'll be less active. It's still pretty warm, even for here this time of year, so I think you'll still see more than a few.
Just past Henderson begins the Atchafalaya Spillway bridge - it's about 20 miles long. Make sure your gas tank is full before you get to it - a wreck on the bridge can cause a complete traffic stoppage lasting quite a long time.