We found a good pitstop on our way back from midcoast maine to NYC last week through reccs on this board.
Southeast Asia Restaurant in Lowell, Mass
343 Market Street 978-452-3182
Its an easy stop off 495 using the Lowell connector, driving directions on their website noted below.
Outstandingly, they serve an extensive all you can eat lunch buffet for $6.95 from 11:30-3 Mon thru Sat. This is a major buffet with a lot of patronage and lots of veg and non-veg choices from their menu of laotian, thai, burmese and other SE Asian dishes. I am sure this is not the best showcase for their cooking but there is some really good fiery stuff out there on the buffet, all labeled (I particularly liked a moderately spicy sparerib dish, khang mhu Ohp, I think, a chicken with ginger and mushroom in coconut milk, a vegetarian green thai curry , and a stir fried bean thread dish and at $7 it is a major bargain, patronized by plenty of the local asian folks, of whom there are many.
Lowell is an interesting town to visit too, and the restaurant is just a couple blocks from the national historic site.