Susan Joseph is hooked on low-fat cooking. So hooked in fact, that Joseph and her husband recently lost a cumulative 45 pounds by shedding cream, butter and excessive cheese from their daily eating repertoire.

Excited about her new cooking style, Joseph spread the word to her Bethesda neighbors, who were interested not only in the weight-loss prospects but in the overall health benefits of a low-fat diet. She started a cooking club, where her friends would jointly prepare a low-fat lunch and share cooking ideas.

Then Joseph, realizing that many local cooks were interested in providing their families with healthier dishes but didn't know how, turned her own know-how (based on nutrition advice from a local dietitian, a long-term interest in cooking and extensive reading) into a formal cooking class.

Now Joseph teaches local cooks how to think differently about family eating. Her guidelines are based on government recommendations and the new American Heart Association diet (announced recently at the AHA meeting here), which all stress lots of fruits and vegetables, low-fat dairy products, breads, cereals and pasta, vegetable oils and low-fat meats.

One of Joseph's primary concerns is teaching family cooks that carbohydrates, such as pasta, are not fattening (it's what you put on it) and how high-fat proteins can be replaced as the centerpiece of the meal. Instead of making a roast the focal point, for instance, Joseph stresses how to use meats in smaller quantities -- diluted in a tomato sauce, in a soup or in a stir-fry.

Her recipes are mostly based on cookbooks, rather than original ideas, but the class deals with how to make easy adaptations of any recipe. Broil meatballs for spaghetti, allowing the fat to drip from the broiling pan. When it comes to saute'ing in butter, cut the amount of fat in half. For instance, while making a steak soup during a recent class, Joseph made the roux with half the quantity of butter and drained the saute'ed hamburger in a colander lined with a paper towel.

Joseph, who says that low-fat cooking is no harder or time-consuming than any other kind of preparation and that all it takes is a little motivation, has other hints for making healthy eating an easier transition for the family:

*Hide unpopular vegetables in foods where your children are least likely to notice them. Defatted chicken soup and stir-fries are a good vehicle for cabbage, and tomato sauces will nicely cover up finely chopped spinach or broccoli.

*Preserve an attitude of curiosity. Make dinner fun by using chopsticks for a stir-fry. Serve pasta in different shapes (wagon wheels, shells, spirals) or different colors (tomato red and spinach green are available at many local supermarkets). Prepare pizza (see recipe below) and serve it with a variety of toppings as in a make-your-own-pizza bar.

*Make low-fat foods that correspond to those from a restaurant. When she makes Chinese or Italian food, her 5- and 11-year-old get "really excited about it," says Joseph.

*Put enough other food on the table, such as bread or fruit, to give the appearance of variety. And don't go overboard on the fact that the food might be different; otherwise children may be hesitant to try it, says Joseph.

*Have the kids help prepare the meal by cutting up vegetables for a stir-fry, for example. Or have them create their own dough shapes with homemade pizza, such as in the recipe below.

This Express Lane can be adapted to your own pizza topping preference. If your family doesn't like artichokes, try mushrooms or sliced green or red peppers, or just eat it plain. You will need salt, flour and sugar already on your shelf, and if you already have one or more of the other ingredients at home, your pizza can have two or more toppings.

EXPRESS LANE LIST: quick-rise yeast, olive oil, whole wheat flour, canned italian plum tomatoes, oregano, part-skim mozzarella, parmesan, marinated artichoke hearts or any other vegetable topping QUICK WHOLE WHEAT ARTICHOKE PIZZA (Makes a 12-inch pizza)

1 ( 1/4-ounce) package quick-rise yeast

1 cup warm water

1 tablespoon sugar

1/2 teaspoon salt

1 tablespoon olive oil

1 1/2 cups unbleached all-purpose flour or more

1 cup whole wheat flour

1 cup drained, chopped, canned italian plum tomatoes

1/2 teaspoon oregano

4-ounce jar marinated artichoke hearts, drained

4 ounces shredded part-skim mozzarella

1/4 cup grated parmesan

Put the yeast, water, sugar, salt and olive oil in a food processor fitted with the plastic blade. Pulse a few times to combine. Remove cover and pour in both kinds of flour. Run the machine continuously until a ball of dough is formed. Remove cover and test to see if dough is sticky or smooth. If it is sticky, add flour and process until smooth. This may require up to 1/2 cup more white flour.

If doing it by hand, combine yeast, water, sugar, salt and olive oil and allow to sit in a bowl for 5 minutes, or until bubbly. Add flours and stir with a wooden spoon for 50 strokes. Since you are doing it by hand, you will get a sticky dough (a smooth dough will require extensive kneading time) that makes a fine crust, but should be spread on the pizza pan with floured hands.

Cover a baking sheet or pizza pan with parchment or nonstick vegetable spray. Turn dough out and spread to make a 12-inch pizza. If using a food processor, you can also divide smooth dough into 6, 10 or 12 pieces and form each piece into a little pizza. Put pizza or little pizzas on prepared baking sheet.

Mix tomatoes with oregano. Pour over dough. Drain artichokes and pour water over them in a colander to remove excess oil. Place on top of pizza. Sprinkle with cheeses. Bake at 425 degrees for 25 to 30 minutes for big pizza or 10 to 15 minutes for the little pizzas, or until the topping is bubbly and slightly brown.