My Burgers are maybe a bit too complicated, but they sure taste good:
2.5 pounds ground beef
1 Finely Chopped Onion.
1/4 Cup Breadcrumbs soaked in Milk
1 TSP Pepper
1TSP Smoked Paprika
6 Fresh Fine Chopped Garlic Cloves
1TBS Malt Vinegar
1TBS Worcestershire Sauce
Mix it all up... then cook a tiny bit in a pan to check the taste and season from there if necessary.
I usually bread the patties in breadcrumbs seasoned with salt, pepper and fresh thyme.
Never had any complaints!