Make the sauce first. In a small bowl, whisk together mayonnaise, sugar-free ketchup, mustard, relish, vinegar, smoked paprika, onion powder, and garlic powder.
Season with salt and pepper. Let it chill in the fridge while you cook to let the flavors meld.
Prep the veggies. Shred the lettuce, dice the onion, chop the pickles, and dice the tomato if using. Keep everything ready to assemble.
Brown the beef. Heat a large skillet over medium-high heat.
Add oil if your pan needs it, then add the ground beef. Break it up with a spatula and cook until browned and cooked through, about 6–8 minutes.
Season the meat. Stir in onion powder, garlic powder, smoked paprika, salt, and pepper. Taste and adjust seasoning.
If there’s excess grease, drain it off to keep the bowl from getting soggy.
Add the onion. Toss in the diced onion and cook for 1–2 minutes to soften slightly while still keeping a bit of crunch. This gives that classic burger feel.
Melt the cheese. Sprinkle cheese over the hot beef and let it melt for 30–60 seconds. You can cover the pan briefly to help it melt evenly.
Assemble the bowls. Divide the shredded lettuce into bowls.
Top each with a generous scoop of the cheesy beef mixture, then add pickles and tomato if using.
Finish with sauce. Drizzle the keto special sauce over each bowl. Start with a couple of tablespoons per serving and add more to taste.
Serve right away. Garnish with extra pickles or a light sprinkle of sesame seeds if you want the “burger bun” vibe. Enjoy while warm.