At Sagra, good, affordable Italian

You got that right: The partners were detectives in the Cambridge Police Department’s major crime unit when they realized their shared passion for food and decided to open a restaurant. (Tavares is still on the job, but Beamud is retired from the force.)

It can be difficult, though, to get a good flow going in a new restaurant — especially one as large as this place (250 seats downstairs and 150 more in its second-floor function rooms). Irregular crowds make adequate staffing hard to plan, yet without it — especially in the kitchen — a good following is impossible to develop. On both my recent Thursday visits, the dining room was very quiet, but the restaurant has been packed on weekends.

Clearly, Sagra’s daily 11 a.m to 6 p.m. special is designed to get people to discover the restaurant (which has a towering billboard of a sign out front) and it’s a fantastic deal: a choice of one of six main courses with a soup or salad, for $10.

The special ravioli al loro piceno ($10) was satisfying and delicious. The dish consisted of big ravioli filled with sheep’s milk ricotta covered in a sweet, bright marinara. The house salad, too, was good: crisp mesclun mixed with some romaine tossed with a light dressing.

The six shrimp in the special (beautifully cooked) shrimp scampi ($10) were served in a flavorful white wine, garlic, and butter sauce over al dente spaghetti. And the day’s soup choice was a rich, homey white bean — its broth thick with pureed vegetables and some grated salami in the mix for a meaty base note.

A dollop of lovely herbed sheep cheese topped the plate of olive oil we were served with bread at lunch.

Good affordable Italian food is what the Sagra owners and chef Adriano Rodrigues say they are aiming for, and lunch hit the bulls-eye.

We didn’t choose as well for dinner.

The best of our choices was a terrific sausage pizza ($11). It had a thin crust, but not too thin, with tasty sweet sausage, a nice red sauce, and good mozzarella. We’re pretty picky about pizza and found this one crave-worthy. We also appreciated being able to have a large side of nicely sautéed broccoli rabe ($4).

I wanted to love the eggplant involtini ($8) appetizer (a kind of eggplant rollup with cheese inside) because the eggplant was sliced as beautifully thin as a crepe and it wasn’t breaded. Alas, the flavors were good, but the eggplant was tough.

The chicken picatta ($15), which our server recommended, would have been very good if there’d been more of the aromatic white wine and lemon sauce in the dish — we had to dig and swish around to get the good flavor. The sautéed spinach on top, however, was deliciously seasoned.

The horseradish aioli that accompanied the grilled salmon ($17) popped with flavor, but the jury’s still out on the salmon, and the rice pilaf was only OK.

The filet mignon ($22) was tender and good, although one of us disliked the rosemary it was sprinkled with. It came with delicious roasted garlic mashed potatoes, and prosciutto-wrapped asparagus that had a great-tasting bacon flavor.

The chocolate lava cake with hazelnut ice cream ($7) had a warm, dark, moist heart, and the evening’s special lemon cake ($4) tasted like it came from one of the bakeries in the North End.

You don’t need to be much of a sleuth to figure out that Sagra’s a great place for a good, inexpensive lunch or early dinner. I’d target a pasta.

JOAN WILDER