Preheat your oven to 400°F (200°C). Scrub the potatoes clean and pat them completely dry. Pierce each potato 4-5 times with a fork. Rub them with olive oil and sprinkle generously with coarse sea salt. Place the potatoes directly on the oven rack and bake for 60-75 minutes, or until the skin is crispy and the inside is easily pierced with a fork.

While the potatoes are baking, heat a large skillet over medium-high heat. Add the ground beef and chopped onion. Cook, breaking up the meat with a spoon, until the beef is browned and the onion is soft. Drain off any excess grease.

Stir in the minced garlic and cook for another minute until fragrant. Add the taco seasoning, tomato sauce, and water. Stir everything together and bring the mixture to a simmer. Reduce the heat to low and let it simmer for 10-15 minutes, allowing the flavors to meld and the sauce to thicken slightly.

Once the potatoes are done, carefully remove them from the oven. Slice them open lengthwise. Fluff the inside of each potato with a fork. Spoon a generous amount of the taco meat filling into each potato. Top with shredded cheese, sour cream, cilantro, and your other favorite toppings. Serve immediately.