I have two deadass favorites
Taco Bueno's party tacos, I usually order 6-8 of these, meat and cheese only. I douse them with Cholula hot sauce as well, damn good
Taco Bell's beefy Fritos burrito, I usually order 1-2 of these, no nacho cheese but add shredded 3 cheese, a metric stuff load of creamy jalapeno sauce, and grilled, forget these are great
I also love really meaty cheese burgers but I don't have any favorites since I love them all so much. My preferred place for a burger though is Steak 'n Shake, I get the triple steakburger with cheese, damn good