Parashas Bo · Passuk 12:8
Chabad.org — English translation + Rashi
Torah Temimah points to Mechilta (verified).
Sefaria — Exodus 12:8
Sefaria — Mechilta
English: “And matzos with bitter herbs they shall eat it” — Scripture tells that the mitzvah of the Pesach is with matzah and maror; and from where that if one has no matzah and maror one still fulfills with the Pesach alone? Therefore it says “they shall eat it.”
In context: See the cited source for the full section.
Derash on the verse (Mekhilta / Pesachim) — not a formal named middah of the 13.
Pesach is eaten with matzah and maror; each can be fulfilled even if the other is missing.