dip, remarry
蘸 centers on briefly submerging something into a liquid: dipping. The remarry sense is a rare, figurative extension of this dipping idea, but its standalone meaning is unclear.
蘸 combines 艹 (grass) with 醮, which likely contributes the sound. The exact historical development is uncertain.
Picture grass 艹 being dipped into a liquid, with the complex lower part 醮 suggesting the container and the act of dipping.
For サン, imagine dipping a sandwich into soup: sandwich -> サン, and the grass-like herbs on top get dipped.