One thing about these food isekai's is the neglect that in many historical societies, being larger/plumper was desirable as a sign of success and luxury. It's only recently that this changed, where being thing was seen as success and luxury as it meant that a person had time to exercise rather than work an office job each day.
And what is it about these and bread yeast? They always get it wrong. Bread yeast and wild yeast exists already otherwise they would only have unleavened flatbread (or rather, crackers/biscuits). What they need to do is make sure they use milk and a tangzong to start the dough as well as a pullman pan. If I see a manga using those, then I'll believe it. Not many people use the tangzong method, but it is used when making a Hokaido milk bread, and because it's a unique technique in our world, I can certainly see that making a big wow in a fantasy world.
Artisanal breads, baked in a stone oven, often have a thick, somewhat hard crust. A lot of those breads are just flour, water, salt and yeast. There was a resurgence of these after the sandwich bread craze.
I suppose I should tag
@N2O and
@Ktoromto since they were talking about the same thing.
I think the antics between the middle brother and the lead is what will keep me reading for a while, rather than anything about the food.