Step 1: Prepare the Taco Beef : Heat olive oil in a large skillet over medium heat. Add the chopped onion and sauté for 2–3 minutes until translucent. Stir in minced garlic and cook for another 30 seconds. Add the ground beef, breaking it apart with a spoon. Cook until browned and no longer pink (about 6–7 minutes). Drain excess fat if needed. Stir in chili powder, cumin, paprika, oregano, salt, and pepper. Add tomato sauce and water, then stir to combine. Simmer on low for 5 minutes, stirring occasionally, until thickened. Remove from heat and set aside to cool slightly.
Step 2: Prepare the Salad Base : In a large salad bowl, combine chopped romaine, cherry tomatoes, corn, black beans, and diced bell pepper. Toss lightly to mix everything evenly.
Step 3: Make the Dressing : In a small bowl, whisk together sour cream, mayonnaise, lime juice, taco seasoning, and a pinch of salt and pepper. Taste and adjust lime or seasoning as desired.
Step 4: Assemble the Salad : Add the slightly cooled taco beef over the salad base. Sprinkle shredded cheese over the top. Add sliced or cubed avocado and crushed tortilla chips. Drizzle the creamy dressing over the salad or serve it on the side. Garnish with fresh cilantro and extra lime wedges.