Prep all your salad ingriedients - chop the lettuce, tomatoes, onoins, avocado, jalapeño, and whatever other toppings you want to use and shred the cheese (if using)
Make the beef. Heat a large skillet over medium-low heat. Once hot, add oil and let it get hot, about 30 seconds. Add onions and salt and pepper and sauté for 4-5 minutes until soft and golden brown. Add ground beef and break it up with the back of a large spoon. Cook for about 7 minutes, adding mustard halfway through and stirring occasionally. Add salt and pepper to taste.
While the beef cooks, make the special sauce dressing. Add the mayo, tomato paste, mustard, pickles, pickle juice, garlic powder, and paprika to a glass jar and stir to combine. Season with salt and pepper.
Once beef is done, assemble the salads. Divide the lettuce, tomato, onions, pickles, avocado, jalapenos, cheese, and ground beef between 4 large bowls. Top with dressing and enjoy!