There's more than one pad thai — the tourist version, the authentic version, and the regional variants.
Sweet, tangy, often with bean sprouts and peanuts prominent — made quickly for high volume; may include ketchup in the sauce (a Bangkok adaptation).
Less sweet, more salty, uses dried shrimp and preserved turnip (chai poh) for complexity; tamarind paste not ketchup; smaller portions.
Pad thai wrapped in a thin egg omelette — a Bangkok street variant; the egg forms a crispy envelope around the noodles; worth seeking out specifically.
Northern pad thai uses thicker rice noodles; coastal areas use fresh seafood; the 'authentic' version depends heavily on where you are in Thailand.
Pad Thai Thip Samai near the Golden Mount is Bangkok's most famous pad thai restaurant — queue at 5 PM, closes when ingredients run out, worth the wait.
