Prep the potatoes by rinsing and scrubbing the potatoes, then peel if desired. Slice into thin fries, about ¼ inch thick, and pat dry with a towel so they crisp better.
Toss the cut potatoes with avocado oil and salt. For extra crispiness, sprinkle with tapioca starch and toss again to coat evenly.
Spread the fries in a single layer in the air fryer basket and cook at 385°F for 15 to 20 minutes, shaking halfway through, until golden and crispy. Work in batches if needed.
Make the special sauce by finely chopping the pickles, then stir together mayonnaise, ketchup, pickles, pickle brine, salt, and pepper until smooth. Refrigerate while everything else cooks.
Mix onion powder, garlic powder, paprika, pepper, salt, and brown sugar in a small bowl. Sprinkle evenly over the ground beef.
Heat a cast iron skillet over high heat. Add the beef and break it up as it cooks. Let some big pieces sit undisturbed so they develop chunky crispy, caramelized edges. Cook until fully browned with some crispy bits.
While the beef cooks, shred the lettuce and chop or slice the tomatoes so everything is ready to assemble.
Assemble the bowls. Add a layer of lettuce to each bowl, top with tomatoes, crispy beef, and hot fries, then drizzle generously with special sauce and add pickles if using. Serve immediately.