Leviticus 5:11-12

11“‘If he cannot afford two turtledoves or two young pigeons, he must bring as his offering for his sin which he has committed a tenth of an ephah of choice wheat flour for a sin offering. He must not place olive oil on it and he must not put frankincense on it, because it is a sin offering.

12He must bring it to the priest and the priest must scoop out from it a handful as its memorial portion and offer it up in smoke on the altar on top of the other gifts of the Lord – it is a sin offering.