My goto burgers that only ever get raving reviews:
Ton of meat
Some eggs (depends on the amount of beef)
Italian style bread crumbs
Paprika
Garlic Powder
Dice an onion
Montreal Steak Spice
Grated Parmesan Cheese
Can throw in some herbs if you like
Mix it all by hand. You can tell if you have enough spice because you can smell it coming out of the bowl.
Sous-vide the shit out of them at 127F for medium-rare. I usually leave them in for ~80-90minutes because I tend to make big patties. Then flash fry em on the grill for color/texture.
On that I personally like to throw some Vermont extra sharp cheddar, goes really well with the burger spices... Otherwise whatever other fixings you like
