Preheat oven to 400°F. Pierce potatoes with a fork, rub with olive oil, and coat with coarse salt.
Bake directly on oven rack for 45 to 55 minutes until fork-tender with crispy skin.
Brown ground beef in a skillet over medium-high heat. Drain fat.
Add taco seasoning, water, and tomato sauce if using. Simmer 2 to 3 minutes until reduced and saucy.
Cut a cross in each potato and press open. Load with taco meat and cheese.
Top with sour cream, pico, jalapeño, olives, cilantro, and lime. Serve immediately.