I don't have a juice for you, but here are some flavors you might try adding to some unflavored nic mix.
Acetylpyridine 1% (PG)
at 10.00 ppm. Cornmeal with a nutty and bready nuance
Perfumers Apprentice - Acetylpyridine 1% (PG)
Popcorn Flavor
this is the flavor of plain popcorn, with no butter notes.
Perfumers Apprentice - Popcorn Flavor
Pie Crust Flavor
this flavor is simply crust, and is great in combination with other flavors. Fruits, nuts, spices...be creative!
Perfumers Apprentice - Pie Crust Flavor
Acetyl Pyrazine 5% (PG)
at 10.00 ppm. Roasted, nutty, bready and yeasty, with popcorn and corn chip nuances
good for graham gracker flavors (enhancer)
Perfumers Apprentice - Acetyl Pyrazine 5% (PG)
(I have some of this on order)
I'm sure some combo might get you something close to bread, but I'm sure that it has been worked on for a while. I could vape yeast rolls all day if they nailed it on the flavor.
That said, though I plan on ordering all of those flavor additives, and I might work on trying to get a bread flavor...I'm not optimistic.
(mildly related picture)