Kosher (or kosher style) deli in Downtown Brooklyn?!
Sometimes I just have to satisfy my jones for a Hebrew National dog crisped up on the griddle or a fat corned beef sandwich. Been to the Pastrami Box by the courts and find them to be pretty good, but they tend to close early and not open at all on weekends - a real favorite with the legal trade.
Used to import from the 2nd Ave. Deli, but alas it is no more :(
Any other venues around Carrol Gardens/Cobble Hill/Park Slope? Would even be willing to bike further afield for a pick up. . .
There is nothing of the sort in the neighborhoods you've specified, other than the recommendations already given. Of course there is are whole Brooklyn neighborhoods full of kosher restaurants out in Borough Park and Midwood, but pretty much all of them serve something other than old-fashioned deli fare.