In a large skillet over medium heat, add the ground beef and cook until browned. Drain any excess fat. Add the diced onion and minced garlic to the skillet. Sauté until the onion becomes translucent (about 3-4 minutes). Stir in the taco seasoning, black beans, corn, and salsa. Cook for an additional 5 minutes until everything is heated through.
In a large mixing bowl, combine the cooked rice, sour cream, and half of the shredded cheddar cheese. Mix well until everything is evenly combined.
In a greased 9x13 inch baking dish, spread half of the rice mixture on the bottom. Add the beef mixture on top of the rice, spreading it evenly. Layer the remaining rice mixture over the beef. Sprinkle the remaining shredded cheese over the top and evenly distribute the crushed tortilla chips.
Place the baking dish in the preheated oven and bake for 25-30 minutes or until the cheese is melted and bubbly.
Remove from the oven and let it cool for 5 minutes. Garnish with chopped cilantro and optional sliced jalapeños before serving.