Heat 1 tbsp. olive oil in a large pan over high heat. Add ground beef and cook until browned. Remove and set aside.
Reduce heat to medium-low. To the same pan add onion, red bell pepper, and sweetcorn, cooking until onions are soft (5-8 minutes).
Add garlic and sauté for 30 seconds, then add taco seasoning. Season to taste with salt and pepper, and stir well.
Return beef to the pan and stir well until combined, cooking for another 3-4 minutes.
In a large bowl, place romaine lettuce at the bottom, add sliced avocado, and top with a quarter of the cooked ground beef and a serving of Pico de Gallo.
Squeeze some lime over the salad, season with salt and pepper if needed, and garnish with fresh cilantro and remaining lime wedges.
