In a large skillet, brown ground beef over medium-high heat. Drain excess fat. Add a packet of taco seasoning. Cook on medium heat until the taco meat is well-seasoned. Set aside to cool.
In a small bowl, mix together sour cream, salsa, and 1/2 teaspoon taco seasoning until smooth.
Chop your salad greens. Rinse and very well-drain all canned ingredients: black beans, sweet corn, black olives, and pico de gallo. If not drained properly, the salad may turn soggy.
In a trifle bowl or large glass dish, layer in this order: lettuce, black beans, seasoned ground beef, pico de gallo, corn, and black olives. Then spread the dressing mixture evenly over the top. Finally, add a layer of cheddar cheese and finish the layers with chopped fresh cilantro.
When ready to serve, top with cubed avocado. Serve the layered taco salad with more fresh cilantro, lime juice, and salsa, if desired.