Pesachim 48B

חמשת רבעים קמח ועוד ⁠— חייבין בחלה. הכי קאמר, קבא מלוגנאי נמי אהאי שיעורא קאי.

Dough made from 5-quarters of a log of flour and a bit more obligates one to separate ḥalla? The Talmud answers that this is what Rav is saying: A kav from Melogna is the same measure as this, as it is not a regular kav but a larger measure, identical to the amount from which one is required to separate ḥalla.

אמר רב יוסף: הני נשי דידן נהוג למיפא קפיזא קפיזא לפיסחא. אמר ליה אביי: מאי דעתיך, לחומרא? חומרא דאתי לידי קולא הוא, דקא מפקע לה מחלה.

Rav Yosef said: These women of our family ordinarily bake kefiza by kefiza, i.e., 3/4ths of a log at a time, on Passover, since it is easier to prevent small quantities of dough from becoming leavened. Abaye said to him: What is your opinion? Do you tell them to do this in order to be stringent? That is a stringency that leads to a leniency, as by working with small quantities one removes the dough from the obligation to separate ḥalla.

אמר ליה: דעבדן כרבי אליעזר, (דתניא,) רבי אליעזר אומר: הרודה ונותן לסל ⁠— הסל מצרפן לחלה. ואמר רב יהודה אמר שמואל: הלכה כרבי אליעזר.

Rav Yosef said to him: They do separate ḥalla from the dough, in accordance with the opinion of R' Eliezer. As it was taught in a baraita that R' Eliezer says: One who removes loaves of bread from an oven and places them in a basket, the basket combines them to reach the quantity from which one is required to separate ḥalla, even if each of the loaves would not attain the necessary measure for separating ḥalla on their own. And Rav Yehuda said that Shmuel said: The halakha is in accordance with the opinion of R' Eliezer. Therefore, the women of Rav Yosef’s household would put all the finished matzot into a basket and separate ḥalla from them.