1. Preheat your oven to 350°F (175°C).
2. In a large skillet over medium heat, cook the ground beef until browned, about 5-7 minutes. Drain excess fat.
3. Add the diced onion and minced garlic to the skillet and cook until the onion is translucent, about 3 minutes.
4. Stir in the taco seasoning mix, diced tomatoes, and black beans. Allow the mixture to simmer for 5 minutes, letting the flavors meld together beautifully.
5. In a 9×13 inch baking dish, layer half of the Doritos, crushing them slightly to form an even layer.
6. Spread the beef mixture evenly over the Doritos, then top with half of the shredded cheese.
7. Add another layer of crushed Doritos, followed by the remaining cheese.
8. Bake in the preheated oven for 20 minutes, or until the cheese is melted and bubbly.
9. Remove from the oven and let cool for a few minutes before topping with sour cream and green onions.

As you prepare this dish, imagine the kitchen filled with laughter and the clinking of forks, much like the gatherings of my childhood. The joy of cooking lies in these shared moments and the memories they create.