Preheat oven to 425° F.
Toss burger bun cubes with olive oil, garlic powder, onion powder, and salt, spread on a baking sheet, and bake 10-15 minutes, tossing halfway, until golden and crisp.
Heat olive oil in a skillet over medium heat and cook vegan ground beef until thawed and heated through, breaking it apart with a spatula. Then add garlic powder, paprika, onion powder, and salt and cook 2-3 more minutes until lightly browned.
To make the dressing, whisk together mayo, ketchup, Dijon mustard, pickle juice, garlic powder, paprika, salt, pepper, and water, adding more water as needed until drizzleable.
Divide romaine among four bowls and top with cooked vegan ground beef, tomatoes, avocado, red onion, chopped pickles, vegan cheddar if using, croutons, and sesame seeds.
Drizzle with dressing and toss lightly before serving.