Brioche bun
Brioche is in 16 recipes and is the current default for anything premium, for good and bad reasons. The enriched dough — butter and egg — is sweeter and softer than a standard bun, which flatters a plain beef patty and fights with anything already sweet, like a BBQ or teriyaki glaze. It also compresses more, so a tall build is easier to eat. The softness is a liability against wet fillings: brioche goes from soft to disintegrating faster than a sturdier potato roll.
Often goes with
Recipes with brioche bun

Foie Gras Luxury Burger

Green Chile Cheeseburger

Zachariah's Shack Burger

The Heisenberg Burger

KFC Classic Chicken Sandwich (Copycat)

KFC Spicy Chicken Sandwich (Copycat)

KFC Smoky Mountain BBQ Sandwich (Copycat)

Viral Bacon Spiral Burger

Fat Mimolette Bacon & Fried Onion Burger

KFC Cheetos Chicken Sandwich (Copycat)

Boneless Wing Stack Burger

Slow Cooker Marry Me Chicken Sandwiches

Bang Bang Burgers

Onion Bomb Burger

Sloppy Smash Supreme

ABQ Hot Chicken Sandwich