Rashi on Leviticus 2:5/רש"י על ויקרא ב׳:ה׳

1ואם מנחה על המחבת AND IF AN OBLATION BAKEN IN THE PAN [BE THY OFFERING], in that one said, “I take upon myself the obligation to bring a meal-offering baken in the pan” (cf. Rashi on previous. verse and Note thereon). This (the מחבת) was a vessel employed in the Temple in which they baked this particular meal-offering on the open fire in oil. The vessel was not deep but flat; therefore the meal-offering made in it was hard, for just because it (the מחבת) was flat the fire burnt the oil. (Menachot 63a). — All of them (i.e. both the meal-offerings prepared in a vessel) require a three-fold use of oil — pouring upon them after they ware prepared, mingling with their dough, and placing of oil in the vessel prior to preparing them (Menachot 74b; cf. Sifra, Vayikra Dibbura d'Nedavah, Chapter 12 1).

2סלת בלולה בשמן FLOUR MINGLED WITH OIL — This teaches us that he mingles them together when they (the cakes) are yet flour (are not yet baked, and not, as might be assumed, when the dough is already formed into cakes, as is the case with לחמי תודה. the cakes of the sacrifice of acknowledgment, Leviticus 7:12, where Scripture prescribes חלות בלולת בשמן, “Cakes” mingled with oil; cf. Sifra, Vayikra Dibbura d'Nedavah, Chapter 12 2).