West Side Kitchen is part diner, part Norman Rockwell luncheonette, and entirely cozy. How is that possible? Well, if Maryanne is working, she’ll give you a cheery greeting and drop off a menu on her way to deliver plates of piping-hot open-faced roast-beef sandwiches ($5.50) on beds of mashed potatoes, overflowing chef salads ($5.70), and heaping bowls of pasta with, say, eggplant ($6.25). Owner Sy Mehdizadeh, meanwhile, will be slow-grilling steak tips for a sub ($5.25/small; $6.25/large) or chicken kabobs ($8.50) so that the meat soaks up the deep charcoal flavor. And if you’re sitting at the counter, you might spot someone else in the exposed kitchen preparing a giant, thin-crust specialty pizza. He could be layering feta, tomato, olive, and basil on a Mediterranean ($8.50/small; $14.75/large), or piling sausage, hamburger, bacon, ham, and pepperoni on a Meat Lover’s ($8.50/$14.75). But by this time, you should probably take a look at the full menu while Maryanne sings oldies and refills sugar dispensers.

West Side Kitchen is a golden oldie — and not just because of the single-serve cereal boxes lined up behind the counter. How many sandwich-and-pizza joints will dish out a glistening, pillowy veggie omelet ($6.25) at three in the afternoon? Sure, it’s only been open since March, but Mehdizadeh owned Supreme Golden Egg on East Broadway for years. So he’s got the tenure — not to mention the perfect-omelet-making dexterity — to create a classic.

West Side Kitchen, 429 Broadway, South Boston | Open Sun - Wed, 5:30 am - 10 pm; and Thur - Sat, 5:30 am to 11 pm | 617.268.0900.