Preheat your oven to 400 degrees. Pierce the skin of the potatoes a few times with a fork so that the steam can escape. Rub lightly with olive oil & season with salt. Bake for 50-60 minutes, or until the potato is done. Set the potatoes aside to cool.
While the potatoes are cooking, make the special sauce. Mix all the ingredients for the sauce together, cover, & refrigerate until ready to use.
Season the ground chuck with the garlic powder & cook in a hot skillet, stirring often, until cooked through. Season to taste with salt & pepper.
Cut the potatoes in half longways. Remove the insides with a spoon. Place the potato skins back in the oven at 400 degrees for about 8-10 minutes, turning halfway, so that they crisp up. Fill each potato skin with warm beef & top with cheddar cheese, if desired. Now, top each potato skin with shredded lettuce, a generous drizzle of speical sauce, chopped pickles and of course - the sesame seeds.