Lucky the person who can find a way to relate work to free-time pursuits. "Jeff" Logan is such a person. Along with her husband, Marshall, she gathers antiques and collectibles. Most are offered for sale in the couple's antique shop on Mt. Pleasant Street. But as Mrs. Logan enjoys entertaining with food, others find their way into the kitchen and dining room of her Adams-Morgan home.

She is devoted to a cast-iron dutch oven and to a cast-iron skillet. Both are uncomfortably heavy, but both transfer heat marvelously well and to her mind cook better. A line of elderly quart and half-gallon preserving jars holds pasta, rice, nuts and seeks. Hard-to-find half-pint jars are marked for herbs and spices. "The round ones are hard to find," she disclosed. "They're $2.50 in the South, but I got one way upstate in New York for 25 cents." A bargain, as they say in the antique trade, is a bargain.

In the center of the dining room there's a handsome refinished butcher block table surrounded by half-a-dozen reconditioned press-back chairs. ("It's hard to find a matching set," Mrs. Logan said, "so we just tried to buy chairs the same height.") A sidboard holds a set of Japanese china, called phoenix ware or flying turkey depending on where in the country you try to buy it. Glasses and potables are stored behind perforated tin doors in a refinished pie safe.

Here Jeff Logan entertains. A working woman, she does so by preference on Sundays or holidays. "I don't have help," she said, "and I like to eat with my guests, so my way is to put my food out on the table and a side table. If I serve a soup, I'll clear away the cups before I put out the rest of the food. But mostly it is ready when the people come to the table."

In summer, when she doesn't entertain much, it may be some unfancy but delicious ribs cooked outside (though she prefers them from the oven) and salads. At other times of the year, the menu will be a blend of recipes she has picked up from newspapers, magazines or cookbooks and traditional foods she grew up with. To her, "European recipes take too much time and some of them are kind of fussy."

The Logans love seafood and dine out appreciatively at restaurants such as Crisfield's in Silver Spring and Lee's in Hyattsville. "I learned most of my cooking just by eating," Jeff Logan said happily. "I kind of add a dash of this and a dash of that. I don't really measure. But it usually comes out all right."

Thus some form of fish will almost certainly be served to guests ("no more than eight"), along with a meat.Appetizers such as stuffed celery and crackers and cheese, salads including a combination of sliced cucumber and onion, a "big" green one and perhaps a cranberry jello mold, and vegetables - baked potatoes and a squash casserole for instance - will be presented. Desert may be a cobbler, one of the few recipes Jeff Logan inherited from her mother "who didn't like to cook," or, since they purchased an antique handmixer, homemade ice cream.

If the fish recipe is complex, the meat dish will be simple, probably a roast. Decoration is important. "I like colorful food," she said. "I use pimiento and green pepper in everthing I can. I like food to be pretty."

She favors lamb over beef to flavor soup stocks and relies on a mixture of sour cream and blue cheese as a condiment for baked potatoes and almost anything else. "Once you try it, plain sour cream tastes like nothing," she declared.

To Jeff Logan, Sunday is a "snack day," so guests - "just people, no one fancy" - come early, around 5:30. There is talk and wine before dinner, but "just a few words after." If she does her favorite bluefish recipe, she will retreat to the kitchen, put it in the oven and spend the 20 minutes it is cooking arranging food on the table and buffet. When the fish is ready, the guests are called to table.

Jeff Logan enjoys shopping so there is little in her freezer except frozen french bread and bagels. It should come as no surprise, as she works with antiques, that modern kitchen tools such as the crock pot don't appeal to her, that her coffee pot and toaster are vintage products, nor that, until a visiting relative gave her a hand-held electric mixer, a rotary egg beater sufficed.

There is only one secret in her kitchen. She won't reveal her given name. "Jeff" is a shortened version of her family name, Jeffers. Her recipes, as you will see, she shares willingly. BLUEFISH LOGAN (Serves 4) 1 bluefish (3 to 3 1/2 pounds), scaled, head cut off and split to the backbone 1/2 lemon Salt and pepper to taste 2 tablespoons butter 1 small onion, diced 1/2 green pepper, seeded and diced 1/2 teaspoon dill weed 1/2 can cream of mushroom soup 1/2 can cheddar cheese soup 1&2 to 1 can (12 ounces) fresh crabmeat Sliced pimientos to taste 2 tablespoons fine bread crumbs

Place prepared fish, skin side down, in a buttered heatproof dish suitable for serving, or a baking sheet. Season with salt, pepper and juice from the lemon. Place in a preheated 375 degree oven. Bake 18 to 20 minutes, or until it will flake.

Meanwhile melt butter and saute onion and green pepper until just tender. Season with dill weed, salt and pepper. Add soups and mix well. When hot add crabmeat to taste. Mixture should not be runny.

When fish is ready remove it from oven and turn control to broll. Spoon crab mixture over fish, decorate with pimiento strips and shake a light coating of bread crumbs over surface. Place under broiler until top has browned. If using baking sheet, slide fish onto serving platter. Serve promptly. For eight, prepare two fish.

BAKED RIBS (Serves 6 to 8) 8 pounds lean spare ribs 3 or 4 bay leaves 1 large onion, sliced 2 ribs celery, broken into pieces 10 to 12 black peppercorns 1 jar (18 ounces) prepared barbecue sauce such as Open Pit 1/4 cup white vinegar, or to taste 2 tablespoons sugar, or to taste Cayenne pepper to taste

Place ribs in a large pot with bay leaves, onion, celery and peppercorns. Cover with water, bring to a boil and simmer for 45 minutes. Leave in pot overnight or for several hours. Drain. Arrange ribs neatly in a heat-resistant dish and pour on a marinade made from barbecue sauce, vinegar, sugar and cayenne. Cover dish and refrigerate overnight or longer. Let dish come to room temperature, then bake uncovered, in a 275-degree oven for about 1 hour.

Note: Jeff Logan prepares barbecued pigs' feet in the same manner, though the preparation takes longer. Boll the pigs' feet for 3 to 3 1/2 hours, or until tender. Cover with marinade and leave two days in the refrigerator. Bake for 1 to 1 1/2 hours. SOUR CREAM CONDIMENT (Makes about 1 1/4 cups) 1 cup sour cream 3 tablespoons blue cheese Salt and pepper to taste

Crumble cheese into sour cream in a bowl. Season with salt and pepper and stir together. Use with baked potatoes, meats, vegetables or as a dip. SQUASH CASSEROLE (Serves 8) 6 medium yellow squash, washed and sliced 1 medium onion, diced 1 medium green pepper, seeded and diced 1 teaspoon salt 1/2 teaspoon black pepper 2 tablespoon butter 2 large or 3 medium tomatoes, washed and sliced 1/2 cup bread crumbs 1/4 cup parmesan cheese Simmer squash, onion and green pepper in 1/2 cup water with salt added until tender. Mash in the pam with butter. Taste for salt and add pepper. Make a layer of the squash mixture in a 1 1/2 quart baking dish. Top with a layer of tomato slices. Repeat layers. Sprinkle on bread crumbs and cheese. Bake in a preheated 375-degree oven until heated through and brown on top, about 15 mnutes. CRANBERRY MOLD (Serves 12 to 14) 1/2 poind cranberries, washed 2 cups water 1 cup sugar 2 boxes gelatin dessert (raspberry or strawberry flavor) 15 marshmallows 1 cup crushed pineapple 1 apple, cored and diced 1/2 cup chopped walnuts

Cook berries in water for 10 minutes. Remove with a slotted spoon. Add sugar, gelatin and marshmallows and stir until sugar and gelatin have dissolved. Pour into a 2-quart mold and chill in refrigerator or by stirring over a mixture of ice cubes and water. As mixture thickens but before it sets, stir in canberries, pineapple, apple and nuts. Regrigerate overnight before serving.