At its best, a Thai meal delivers a balance of spicy, salty, sweet, sour and bitter, a harmony of flavor marked by fresh ingredients and a range of textures.

And at Thai Sawasdee in Groton, although there are hits and misses, overall that's exactly what's on the menu.

In two visits, we sampled a range of dishes — soups, salads, noodle and rice dishes including larb, lad nah and curry — and, with a couple of exceptions, found them delightful.

The service, however, was another story.

Our first visit was for dinner on a Monday night. We joked about the help-wanted sign in the window, laughing that it might not be the best night to come for dinner.

Indeed, there was only one waiter on duty. A sullen cashier also manned the dining room, but she seemed restricted to seating guests and to taking and serving take-out orders.

We were celebrating my 55th birthday, and my three guests were from 5 to 13 years older than I am. Yet, with a wink and a nod, the waiter carded us, one at a time. Charming or annoying? Hard to say.

But what followed was an almost comical series of service blunders.

One among us spent some time with the wine list and ordered a glass of the featured Clos du Bois chardonnay, only to be told they didn't have that wine. No substitution was offered. 

Another diner ordered the Me Grob as an appetizer.

"We don't have that anymore," he was told.

For an entrée, the wine drinker chose from the Chef's Specialties section of the menu, Basil Clam, $13.99, described as "stir-fried clam in hot chili paste with basil, onions, bell pepper, mushrooms, green beans & scallions." Later, with the rest of us having already been served our meals, the waiter, clearly flustered, returned to say the restaurant was out of clams and to ask what he would like in his dish instead.

He chose seafood and was quickly rewarded with a huge portion swimming in a rich, dark, sea-bottomy sauce. There were squid and shrimp, but the mussels were the stars. Giant and tender, they were larger and flatter than our local blue variety, but they were fresh, sweet and delicious.

We had started our meal with summer rolls, $4.99, from the regular menu, and crispy duck salad, $7.99, and chicken satay, $6.99, from the specials board. 

The summer rolls were run-of-the-mill, fresh but not unique, with a clear, sweet peanut sauce on the side. The crispy duck salad was large, with an iceberg lettuce base, fairly typical for Thai cuisine. It included scallion, carrot and cucumber slices, all fresh, crisp and cold, with chunks of warm, salty duck served on top. But the duck, although crispy, was dry and overcooked.

The chicken satay, however, was tender, moist and full of flavor, the clear winner of the three appetizers. But we had devoured half of them before our waiter arrived with a sauce — a clear, sweet oniony liquor — that was meant to be served with them.

Our other three entrees were chicken larb, $9.99, and basil chicken, $9.99, from the regular menu, and yam yellow curry, $9.99, from the specials.

The larb — a chopped meat salad — featured minced white meat chicken in a tangy, cilantro-forward dressing. The meat had been hot when it had been placed on the lettuce, but it was only warm when it arrived at the table. There was some baby corn and some broccoli, but overall it was disappointing.

The basil chicken's rich brown sauce was slightly sweet, and the dish was loaded with that tender chicken, fresh green peppers and green beans. But the yam yellow curry was a triumph in what I can only imagine must be Thai comfort food. It was piping hot, creamy with coconut, slightly sweet and beautifully spiced, full of sliced yam, thin carrot coins with fancy, scalloped edges, and plenty of whole cashews. The portion was huge and, at the end of the meal, there was none left to bring home. 

It's worth mentioning that the bill for the four of us, with drinks, topped $100 only by 95 cents, a real bargain for the obvious care and attention to detail that clearly went into nearly everything we ate.

On another day for lunch, the specials were largely the same. We ordered the spicy beef salad, $6.99, and lad nah with shrimp, $7.99, from the regular menu, and the pumpkin curry, $6.99, from the specials.

The meal began with a complementary cup of clear soup, clean but mildly flavored with a striking melon background note. It was a delicious warmup.

The spicy beef salad featured warm, tender slices of beef with a terrific grill flavor and an umami backdrop that hinted of fish sauce. It shared the plate with iceberg lettuce, cucumber, tomato, carrots and red onion, with a sprinkling of cilantro leaves and scallions.

The wide flat noodles in the lad nah were perfectly tender and chewy, mingling with bits of scrambled egg, fresh vegetables and shrimp in a light, mildly spicy but very flavorful brown sauce. The portion was generous, and we ate it all.

The pumpkin curry was hotter than its yam cousin, but not overly so — I'd rate it medium spicy. The accompanying pile of fried rice included egg and peas. The pumpkin chunks were starchy and tender, delicious with the spicy sauce, moist chicken and fresh vegetables.

Unfortunately, before we left but thankfully after we had finished our meals, another staff person began mopping the dining room floor with a powerfully pungent disinfectant.

Perhaps it's telling that during our dinner visit, a robust take-out business was also being conducted in the dining room. Some customers were hanging out, waiting for their orders. Another stopped mid-order to use her cellphone and loudly ask what the person at home wanted for dinner.

Maybe, until that help-wanted sign comes down, take-out is the best way to enjoy the delicious, authentic offerings coming out of the Thai Sawasdee kitchen.

j.blanchette@theday.com

Thai Sawasdee

762 Long Hill Road, Groton

(860) 448-8424

Cuisine: Thai 

Atmosphere: Asian bistro 

Service: Friendly 

Prices: Entrees run $8.99-$15.99, depending on your choice of protein. 

Hours: Monday through Thursday, 11 a.m.-9 p.m.; Friday, 11 a.m.-10 p.m.; Saturday, noon-10 p.m. 

Credit cards: Yes 

Reservations: Not needed

Handicapped access: One step up from parking lot to sidewalk. Otherwise everything is all on one level.