The Lower East Side has no shortage of ambitious restaurants, and several spots here draw diners from all over the city and the world. But if you want to find the best place in the neighborhood, you need only look where the area’s residents go, and they’re filling the seats and barstools at Cafe Katja. In its early days, when the restaurant occupied what was essentially a glorified hallway, the place wanted to serve just sausages and Austrian beer. Over time, fueled by the culinary ambition of one of the owners, the menu has expanded to include well-executed and comforting dishes like cabbage salad, warm smoked salmon, schnitzel, and spätzle, plus a raft of white asparagus dishes when the season is right. The space has grown, too — Katja has tripled in size thrice since opening, and still you might have to wait for a table. No matter. Chat up the staff over a Stiegl at the bar; they’ll remember you when you return. That’s why this place rolls so deep in regulars.