Make the sauce: In a small bowl, whisk Greek yogurt, mayo, ketchup, mustard, pickle juice, garlic powder, onion powder, and paprika.
Season with salt and pepper. Adjust thickness with a splash of water or more yogurt. Refrigerate while you cook the beef.
Brown the beef: Heat a large skillet over medium-high.
Add the ground beef and cook, breaking it up with a spatula, until mostly browned, 4–5 minutes. Drain excess fat if needed, leaving about 1 teaspoon in the pan.
Add aromatics and seasonings: Stir in diced onion and cook 2–3 minutes until softened. Add garlic, tomato paste, Worcestershire, smoked paprika, mustard powder, salt, and pepper.
Cook 1–2 minutes more until fragrant and glossy. Taste and adjust salt or acid (a splash of pickle juice works wonders).
Prep the base: While the beef finishes, assemble bowls with chopped greens. If using grains or cauliflower rice, warm them and add a scoop to each bowl.
Layer the toppings: Divide the seasoned beef among the bowls.
Top with shredded cheddar so it melts slightly on the warm beef. Add tomatoes, pickles, red onion, and avocado if using.
Finish with sauce: Drizzle the special sauce over each bowl. Add fresh-cracked black pepper or a sprinkle of sesame seeds if you like a “burger bun” nod.
Serve: Eat immediately while the beef is hot and the lettuce stays crisp.