“When anyone brings a grain offering to Yahweh, the offering shall be of choice flour. The worshiper shall pour oil on it. He shall put frankincense on it. He should bring it to Aaron’s sons, the priests. After taking from it a handful of the choice flour and oil, with all its frankincense, the priest shall turn this token portion into smoke on the altar, an offering by fire of pleasing odor to Yahweh. What is left of the grain offering shall be for Aaron and his sons. It is a most holy part of the offerings by fire to Yahweh.”
While it is possible that the wandering Hebrews might have herds and flocks, it is more difficult to think that they were able to grow crops unless they stayed in one place for some time. However, flour seems to be plentiful. They make an offering of choice flour. The worshiper puts oil and frankincense on it. Then they bring it to Aaron’s sons, the priests. Once again this is an offering by fire that has a pleasing odor for Yahweh. Whatever is left over goes to Aaron and his sons.
“When you present a grain offering baked in the oven, it shall be of choice flour. Unleavened cakes mixed with oil, or unleavened wafers spread with oil. If your offering is grain prepared on a griddle, it shall be of choice flour mixed with oil, unleavened. Break it in pieces and pour oil on it. It is a grain offering. If your offering is grain prepared in a pan, it shall be made of choice flour in oil. You shall bring to Yahweh the grain offering that is prepared in any of these ways. When it is presented to the priest, he shall take it to the altar. The priest shall remove from the grain offering its token portion and turn this into smoke on the altar, an offering by fire of pleasing odor to Yahweh. What is left of the grain offering shall be for Aaron and his sons. It is a most holy part of the offerings by fire to Yahweh.”
This grain offering should be baked in an oven with choice flour. Whether it is unleavened cakes or wafers it should have oil spread on it. It could be either baked in an oven, or prepared on a griddle or a pan. After the pleasing odor for Yahweh of this grain offering burnt on the altar, what was left of the grain offering shall be for Aaron and his son. This was one of the benefits of being a priest.
“No grain offering that you bring to Yahweh shall be made with leaven. You must not turn any leaven or honey into smoke as an offering by fire to Yahweh. You may bring them to Yahweh as an offering of choice products, but they shall not be offered on the altar for a pleasing odor. You shall not omit from your grain offerings the salt of the covenant with your God. With all your offering you shall offer salt.”
There cannot be any leaven or honey in any of the grain offerings for Yahweh. You could bring leavened or honey products but they could not be offered as grain offerings. You also had to use salt in your grain offerings. There is a big emphasis on this being unleavened bread and the use of salt. The unleavened bread harkens back to the exodus Passover event in the book of Exodus. Honey was associated with foods that ferment. Salt had to do with agreements and the practice of eating a salt seasoned meal together after an agreement was reached.
“If you bring a grain offering of first fruits to Yahweh, you shall bring as the grain offering your first fruits, coarse new grain from fresh ears, parched with fire. You shall add oil to it and lay frankincense on it. It is a grain offering. The priest shall turn a token portion of it into smoke. This can be some of the coarse grain and oil with all of frankincense. It is an offering by fire to Yahweh.”
You have to remember that the grain offering was not considered as good as the animal offering as indicated in the story of Cain, the farmer, and Abel, the shepherd. Yahweh liked the shepherd sacrifice better than the grain sacrifice. Everything had to be first class for these sacrifices. Frankincense and oil played a major role. Both of these products must have been common enough for people to use them. The grain offering could be baked, roasted, or parched as long as oil and frankincense was involved.