Claiming Bakery/Home-baked loaves of bread which were discovered on public/private property, by their identifying characteristics: Bava Metzia 23a, 25a
Bakers
An expert baker, Baytus ben Zonin was able to make bread in the form of designs for Pesach without fear of it becoming Leaven: Pesachim 37a
Rav Papi allowed the bakers of the Reish Galuta [Exilarch] to put dried, burnt grain into cooking food on Pesach: Pesachim 40b
Rav Huna bar Chiyya's son, Levi, found the family baker mixing grain and water for animal fodder on Shabbat, and rebuked him, until Rav Huna bar Chiyya pointed out that the baker's method was correct: Shabbat 156a