The porch remains one of the great institutions of Washington. As a place to relax and watch the world go by, preferably while gossiping with friends, it is unrivaled. The fact that our particular porch (a balcony) is minuscule does not deter us from entertaining outside at least six months in the year.

Some form of sustenance besides a cooling drink is clearly indicated and I've gradually built up a repertoire that stretches from home-toasted nuts to the easy hors d'oeuvres that follow.

The onion tarts are similar to those sold by the local charcutier in the market near our home in France. Some days he adds olives, anchovy or spicy sausage, but I like them best quite plain so as to appreciate the full sweetness of the onions, and prefer to add just a touch of parmesan cheese and cream to keep the topping moist during baking.

Next is a tortilla that is not Mexican, but a Spanish-style omelet cooked over the lowest possible fire so the eggs set without being dry. All manner of flavorings are possible and I'm particularly fond of the trio of blue cheese, walnuts and parsley, a combination from the roquefort country of southwest France.

Last comes a very American idea, with baby new potatoes acting as a base for sour cream and a variety of toppings from bacon to caviar, chutney and peanuts. The sour cream is mixed with cream cheese so it does not run, and guests are left to create their own combinations.

Each of these hors d'oeuvres can stand alone, and together they add up to a simple meal if served with a green salad.

Onion Pastry with Tomato Blue Cheese and Walnut Tortilla New Potatoes with Sour Cream Suggested Drink: spritzer made of German or domestic riesling white wine mixed directly in the glass with an equal quantity of chilled club soda Timetable

For the cook with a busy schedule, the pastry can be baked ahead, leaving simple preparations before guests arrive.

Up to 2 days ahead: Bake onion pastry and refrigerate. Chill wine and club soda.

Up to 2 hours before serving: Cook tortilla and keep at room temperature. Boil potatoes and prepare sour cream and flavorings; keep at room temperature.

Twenty minutes before serving: Heat oven and warm onion pastry.

Just before serving: Cut tortilla and onion pastry in squares.

ONION PASTRY WITH TOMATO (8 servings)

A half teaspoon of dried red pepper flakes can be added to the cream mixture instead of cheese.

FOR THE PASTRY DOUGH:

2 cups flour

1/2 teaspoon salt

1/4 cup ( 1/2 stick) butter

1/4 cup shortening

3 to 4 tablespoons cold water

FOR THE FILLING:

2 tablespoons olive oil

6 sweet onions (2 pounds), thinly sliced

Salt and pepper to taste

1 egg

1/2 cup whipping cream

3 tablespoons grated parmesan cheese

1 1/2 pounds tomatoes, peeled and sliced

For the pie pastry: sift flour with salt into a bowl and add butter and shortening. Rub in fat with your fingertips until it resembles crumbs. Mix in water, adding enough so dough forms a ball that is soft but not sticky. Press it together lightly and chill 15 minutes.

In a saucepan, heat half the oil and add onions with salt and pepper. Press a piece of foil on top, add the lid and cook very gently, stirring occasionally, until onions are very soft, 20 to 25 minutes. Remove cover and foil and cook until all moisture is evaporated and onions are lightly caramelized. Taste for seasoning and let them cool.

Roll out pastry dough to a 14-inch square, put on a greased baking sheet and roll a shallow border around edges of pastry. Whisk egg with cream until mixed, stir in cheese and black pepper. Spoon mixture evenly over pastry and spread onions on top. Note: If onions are warm they will melt dough. Top with tomato rounds and sprinkle with remaining oil, salt and pepper.

Bake pastry in a 400-degree oven until crisp and brown, 25 to 30 minutes. Serve warm or at room temperature. Onion pastry is best eaten the day of baking, but it can be kept up to 2 days in the refrigerator. Reheat it in a low oven 10 to 15 minutes and cut it in squares for serving.

BLUE CHEESE AND WALNUT TORTILLA (8 servings as an appetizer)

An excellent quick supper dish, as well as an hors d'oeuvre.

10 eggs

1 cup parsley, chopped

Freshly ground black pepper and salt to taste

2 tablespoons butter

3 ounces walnuts, coarsely chopped

5 ounces blue cheese, finely crumbled

Whisk eggs in a bowl until frothy and completely mixed. Stir in parsley and black pepper and salt if needed (note: the cheese may provide enough salt).

Heat butter in frying pan until foaming but not browned. Add walnuts evenly over bottom, pour in egg mixture, and top with cheese. Lower heat and cook as slowly as possible until center of tortilla is almost set, 15 to 20 minutes. Finish cooking under the broiler, about 30 seconds. Let cool to tepid, then turn out onto a platter so the browned side is upwards.

Tortilla can be cooked up to 2 hours ahead. Cut it in squares and serve with toothpicks or forks.

NEW POTATOES WITH SOUR CREAM (8 servings)

Select the smallest possible baby potatoes for topping with sour cream and a variety of flavorings. Pumpernickel bread is a quick alternative to potatoes.

2 pounds baby new potatoes, unpeeled

1/2 pound bacon

3/4 cup roast peanuts

3/4 cup mango chutney

Bunch chives, coarsely chopped

4 ounces red caviar or black caviar

1 cup unsweetened shredded coconut

1 cup sour cream

1 cup (8 ounces) soft cream cheese

Black pepper to taste

Put potatoes in a pan of cold salted water, cover and simmer until just tender, 10 to 15 minutes. Drain potatoes and let cool. Cut them in half lengthwise, pile in one or two bowls and cover.

Dice bacon, fry until crisp and drain on paper towels. Crush peanuts with a rolling pin. Work chutney through a coarse sieve, or chop it on a board until pure'ed. Put bacon, peanuts, chutney, chives, caviar and coconut in small bowls and cover.

Beat sour cream into cream cheese until smooth. Add pepper to taste, pile in one or two bowls and cover. Potatoes, flavorings and sour cream can be prepared 2 hours ahead and kept at room temperature. Uncover just before serving.