Heat olive oil in a skillet over medium heat. Sauté the sliced red onion until soft and slightly caramelized, then remove and set aside.
In the same pan, add ground beef and season with garlic powder, onion powder, salt, and pepper. Cook until browned and cooked through.
In a small bowl, whisk together the mayonnaise, ketchup, mustard, pickle juice, salt, and pepper to create the burger sauce.
To assemble the bowls, start with a base of chopped romaine lettuce. Add cherry tomatoes, sliced pickles, finely chopped red onion, shredded cheddar cheese, cooked beef, and sautéed red onion.
Drizzle with the burger sauce and serve immediately.