Great Challah in Brooklyn?
The gas-station Ostrovitsky's, yes indeed, it's a Kosher bakery...everything looks like it's delievered fresh daily and the selection is more extensive at the flagship location.
Items I've tried are the challah (definitely high-test), their hamantashen (89-octane) around Purim and miscellaneous fancy cookies.
OK, Chowhounds, I'm going to let the cat out of the bag...
OSTROVITSKY's Bakery (yes, the one on Avenue J) has a branch on 14th Avenue near 37th/38th Street on the edge of Borough Park...can't find it?...well there it is, right inside the RIO gas station's storefront!
Challah of the highest order...and not as far from home for the 'Slopers. In fact, a quick walk over from the Church Avenue "F" train or the B67 (Seventh Avenue to McDonald Avenue/Cortelyou Road) bus. If nothing else, a good geographical mind-expansion and a quick look at the homes of Kensington. Ostrovitsky's is closed on Shabbos and holidays.