A long while ago I wrote a rapturous review of the roast beef dip at Roll n'Roaster, and one of the replies recommended the 'better' beef on weck sandwich at Bonnie's Grill in Park Slope. I'm never in that area of Brooklyn, so it took me all this while to finally haul my bum to Bonnie's. I'm sorry to say that I wasn't won over.
Some of my beef with Bonnie's version of the french dip probably has more to do with personal preference than any true fault of the sandwich, but there were a few definite flaws. First, the sandwich was too big. Before someone jumps all over me, let me point out that this is very similar to the small burger (In n Out, Shake Shack, Burger Joint) vs. large burger (McHale's) debate. I myself go for the small burger, as balance of flavors is more important to me than pure beefiness of a huge patty. The Bonnie's sandwich was so large, it was difficult to handle and bite into.
Something was definitely not right about the beef. Cut thick, rather than thin, the slabs of beef could barely bend onto the roll. But the true fault was that the taste was lacking -- not enough roast beefy flavor. I couldn't figure it out at first; I'd take a bite and think, take another bite and think. Finally, I figured out that I was chewing but not tasting anything. All texture, no flavor. It was strange, as there was plenty of meat, not overcooked and plenty juicy. But totally tasteless.
To add insult to injury was the bun, which was a regular kaiser roll with caraway/rye seeds. The seeds imparted a strange medicinal aftertaste, but even worse was that the beef juice made the bun completely soggy, and it disintegrated like a wet paper towel before my first bite.
There was one really good thing about the sandwich: the dollop of very spicy horseradish plopped on top, which imparted the only flavorful bites I enjoyed from the sandwich. I finally ended up eating the horseradish-ed parts, and left the rest of the sandwich on my plate. (This is unusual for me, since I normally clean my plate till no trace of food or sauce remains.)
That said, no complaints about Bonnie's in general. Nice comfortable pub-type setup. Sitting at the counter gave me a ringside view of the efficient food prep. Service was prompt if not super-friendly. Functional. Rest of the food looked pretty good, so I will probably stop in again, but not for the beef on weck.