For years now I've claimed to make the world's best chopped liver and the lightest, tastiest matzo ball soup. But after our recent trip to the Delly Denm Potomac I may turn in my chicken pot. The food was good - yes, even the liver and the soup - the portions were large and the prices were moderate.

Deciding what to do wasn't easy. To reach the dining rook we walked by cases of great looking meats and salads and two cases full of bagels, breads and faney dessets. The menu goes on for four pages.

Three of us began with soup. The chicken noodle at 75 cents, was good and did not appear to be the canned variety. The chicken matzo ball soup, 80 cents, my husband says, was as good as the soup I make I didn't think so but yielded to a more objective source. The borsht 80 cents, came with too much sour cream already mixed into the soup.

We all tried a little of an appetizer called stuffed derma for $1.50. It is the skin of a chicken neck filled with a seasoned bread stuffing. We had never eaten it before and found it rather bland and too filling for a first couse.

Then on to the salad bar which is included with any order over $2. The offerings were crisp and fresh and the selection better than most. Even our 3 year-old daughter, who isn't a big salad [WORD ILLEGIBLE] enjoyed a bowl of fresh bean sprouts and some macaroni salad. The cherry tomatoes were red, with very good bean salad and dressings.

"I get full just looking at this," said our friends' daughter, 7, who is the food reporter for her second grade class newspaper. She had just finished her soup and salad when her potato latkes (pancakes) arrived with a large bowl of applesauce. Her parents selected the items from the appetizer menu for 1.75. There were three large pancakes and any adult having soup and dessert would probably find it plenty. The latkes were crisp and hot and had a good potato flavor.

Her parents ordered well for themselves too. They gave us a good report on the cheese blintzes, $2.75, and the "Pastrami Commie," a hot pastrami sandwich on rye with coleslaw and a Russian style house dressing. It was big and good and cost $2.55.

My husband was the big eater. He ordered a beef brisket platter for $4.95. The menu said it's served with kasha and gravy, but he asked for and was served potato pancakes. He thought they were delicious but the peas and carrots were very ordinary.

I ordered a chopped liver salad plate called the "Thin Lady," for $3.45. The liver really was very good, smooth and mild with a taste of onion. But it wouldn't keep anybody thin. There was enough liver for at least two people, a hard boiled egg, two corn muffins and lots of lettuce, tomato, raw onion and cucumber.

For our daughter I ordered a bagel, her favorite food. It was served with lots of cream cheese and she was happy and full for only 50 cents. Our son Dan. 1 1/2, liked his kosher hot dog so much that I've been buying them for him ever since. Both children enjoyed large glasses of orange juice for 60 cents each.

In spite of all we'd eaten we couldn't leave without trying at least two desserts. Our friends decided to share the cheesecake and my husband ordered black forest cake. The cheese cake, $1. was good but not exceptional.

The black forest cake, for only 95 cents, turned out to be the best part of our meal. We asked for some extra plates and cut the huge piece of cake so that we all had a portion. It was delicious chocolate and vanilla cake laced with rum, with whipped cream, shaved chocolate and cherries on top. The pieces of cake can be purchased at the bakery section in the front of the restaurant and just two pieces would easily feed six.

The menu also included a variety of hamburgers ranging from $1.15 for a plain quater-pound of meat in a pita bread with lettuce, tomato and raw onion. There are eight varieties of bagels.

Our waitress was pleasant and generally prompt and brought all the extra plates and glasses we asked for. There were high chairs and booster seats for children who needed them, as well as good food.

The bill for all seven of us, including tax, was $24.99.

The Delly Den. 7913 Tuckerman Lane in the Cabin John shopping center. Open seven days a week. Sunday through Thursday, 10 a.m. to 10 p.m. Friday and Saturday, 10 a.m. to midnight. Carry-out service. No credit cards. Ample parking. Accessible to the handicapped.