Historical clue formulations

• Classic lunchbox staple, informally — 2025-09-19
• Three-ingredient lunchbox staple, familiarly — 2021-05-24
• Something that might be packed with juice, informally — 2019-04-21
• Popular sandwich, informally — 2017-04-10
• Easily prepared lunch item, informally — 2014-07-31
• Sack lunch staple, for short — 2014-06-15
• Popular sandwich, informally — 2005-08-19
• Lunchbox item, for short — 2003-10-25