Cut the peeled onion in half, and then slice to your desired thickness.
In a large skillet over medium-low heat, heat olive oil.
Add the onion, stirring to coat them in the oil. Cook on medium low heat.
After 7-8 minutes, add salt and sugar, continue to cook, stirring every few minutes.
Keep the heat low, and add water as needed, to keep the onions from drying out.
Cook for 30 minutes or more until the onions are a rich caramel color.
In a small bowl, whisk together all the kimchi sauce ingredients.
Heat 30ml of oil on high in a non-stick pan.
Add the defrosted Big Fry Burgers and reduce to medium heat.
Fry for 9 minutes, turning occasionally
Spread kimchi sauce on toasted buns.
Top with lettuce, then the Big Fry Burger patty.
Add two tablespoons peanut butter to each burger patty, top with a generous amount of caramelized onions.
Add more lettuce, a few tablespoons of mashed avocado, and several tablespoons of kimchi sauce, place the bun on top, and enjoy!