I always thought a taco implied a hardshell. At least in the US, I grew up with the crispy yellow pre-folded U-shaped shells that were stuffed to the brim with ground beef, iceberg lettuce, flavorless tomatoes, and buried in orange cheddar cheese. Only after visiting Mexico (a lot), I learned, or at least I thought I did, that truly authentic tacos consist of double-layered soft corn tortillas -- each no bigger than 6-inches in diameter -- dotted with a sprinkle of meat. Turns out this was wrong, too. The contrast of authentic tacos being smaller in size with a soft shell versus the oversized crispy-shell impostors is overly simplistic. The texture, size, shape, and filling of authentic tacos varies tremendously. Some of Mexico's most delicious tacos are in fact hard-shelled, native to regions like Los Mochis and Baja California Sur.