Tempura can be a dodgy choice at Japanese restaurants. More often than not, it arrives with an overly thick, doughy coating and an excess of oil. I was delighted recently to find a first-rate version at Lou’s Sushi on P Street—the tempura arrived, arranged prettily on a cute little curved wooden dish, featuring one of the most delicate, crunchy and enticing coatings I have ever encountered. The individual pieces were not greasy, and I was impressed with the range of items offered, from zucchini slices and asparagus stalks to green bell pepper and sweet, sturdy onion rings. Pair this delectable small plate with one of Lou’s delicious and refreshing cold sakes.