Saute 2 cups onions in 2 tsp olive oil over medium high heat, stirring frequently until onions are dark, about 15 minutes. Season with kosher salt.
Combine the 12 oz Hungry Planet Beef™ and caramelized onions in a large bowl. Season with salt and black pepper. Form into 4 equal patties.
Prepare the secret sauce, puree 1 ¼ tsp doenjang with 1 1/2 tsp ketchup until smooth. Add the remaining 1 1/2 tsp ketchup and ⅓ cup mayo, then puree until smooth and blended.
Sear patties in hot oil for 2 minutes. Turn over, top with cheese and sear for 2 minutes.
Toast 4 buns and spread with secret sauce. Place pickle slices on bottom. Top with burger, tomato and bun.