Prepare the baked potatoes; set aside to cool for at least 10 minutes.
Meanwhile, heat a large skillet, over medium heat, and add the ground beef, diced onion and minced garlic; season with salt and pepper; cook until no longer pink, breaking up the meat with a spatula; drain.
To the ground beef, add the taco seasoning, water and salsa; stir to combine then bring to a simmer over medium heat; cover and reduce heat to low; simmer for 15 minutes; if there is too much liquid, simmer with the lid off for a bit.
Gently slice open potatoes lengthwise and squeeze the sides to open, careful not to let them break in half completely.
Season the potato with salt and pepper and mash with a little sour cream.
Divide the taco meat among the potatoes and top with freshly shredded cheddar, green onions or any of your favorite taco toppings.