Flour

Use a scythe to cut wheat to get bunches of wheat from a wheat field, grind it to flour in a millstone.
Also used in the process of making bread and cakes, use it with water from a trough or bucket to turn it into a Lump of Dough and mix with milk to make a Lump of Cake Dough.

For those with no skill at farming a trip to the pirate kitchen in the upper reaches of Nargor will yield both flour and lumps of dough. You can also find more than 594 flour in the Dream Realm, here close to The Dream Master.
It looks the same as Fungus Powder and Sugar. 1 of these is needed in The Scatterbrained Sorcerer Quest.
24 of these are needed in the What a foolish Quest.
15 are needed in the Hot Cuisine Quest.
2 are needed in the Blood Brothers Quest.

The weight was changed from 5.00 oz to 1.00 oz on the Update 8.5.
It happened basically to avoid confusion with how many units of flour are needed in The Scatterbrained Sorcerer Quest and because flour is actually really light and shouldn't weigh as much as a fish.^[1]