Chabad.org — English translation + Rashi
Torah Temimah points to Toras Kohanim (Sifra), Vayikra Dibbura DeNedavah, on 2:4 (maafeh tanur — not other ovens).
Sefaria — Sifra / Toras Kohanim, Vayikra Dibbura DeNedavah
English: “Baked in an oven” — and not baked on a kupach, nor on tiles, nor in Arabian pots.
Miyut of the oven type — only a proper tanur qualifies for this form of minchah.
Only a proper tanur qualifies; alternative baking surfaces are excluded. The Sifra reads “baked in an oven” as limiting the preparation to a genuine oven and excluding baking on a kupach, on tiles, or in the pots associated with Arabian practice.