Caramelize the onions. Heat the olive oil over medium-high heat in a medium heavy-bottomed skillet. Add the onions, season with 1 teaspoon sea salt, and sauté for 15 minutes until soft and golden brown, adding water as needed to keep the onions from burning.

Preheat the grill to high heat.

Make the patties. While the onions are cooking, mix together the ground beef, 2 teaspoons sea salt, ground black pepper, and 1 ½ tablespoons teriyaki sauce in a large mixing bowl until a homogeneous mixture is achieved. Form the mixture into 4 patties and set aside.

Grill the burgers. Place the burgers on the grill and cook for 3 ½ minutes on either side.

Rest. Remove the burgers from the grill and allow them to rest for 5 minutes.

Serve. Sandwich each patty between a bun along with 1 pineapple ring, ¼ of the caramelized onions, and 2 tablespoons of teriyaki sauce.