Taco Bell offered Bucket Nachos (or Bucket Nacho according to the actual bucket) which as far as I can tell is a bucket of nacho/tortilla chips without cheese i.e. it's a bucket of chips... from what I can guess, it looks like you can choose to sprinkle them with Barbecue, Nacho Cheddar, or Ranch seasonings or just eat them plain.
It is also entirely possible that the cheese just comes in a dipping cup on the side (it's just not shown in the promo shot). I haven't been able to find out much from digging online other than it's a bucket of corn tortilla chips though.
It's 99 pesos per bucket or about $2.42 US.