Step 1: Cook the Taco Beef : Heat olive oil in a large skillet over medium heat. Add the diced onion and sauté for 2–3 minutes until softened. Add minced garlic and cook for 30 seconds, until fragrant. Add ground beef and cook until browned, breaking it up with a spatula. Drain excess fat if necessary. Stir in taco seasoning and water, then simmer for 2–3 minutes until thickened. Season with salt and pepper to taste, then remove from heat and let cool slightly.
Step 2: Prepare the Salsa Dressing : In a small bowl, whisk together salsa, sour cream, lime juice, olive oil, chili powder, salt, and pepper. Adjust the flavor with more lime juice or spice as desired. Chill until ready to serve.
Step 3: Assemble the Salad : In a large salad bowl or individual plates, arrange a base of chopped lettuce. Add black beans, corn, cherry tomatoes, bell pepper, avocado, cheese, and onion. Spoon the warm taco beef mixture over the top. Drizzle with salsa dressing. Garnish with crushed tortilla chips and fresh cilantro if desired.
Step 4: Toss and Serve : Toss lightly just before serving to coat everything evenly with the dressing. Serve immediately while the beef is still warm for the best flavor and texture.