An Apple Betty for young cooks to make

This is a kind of Apple Betty that is easy to do, delicious to eat, and takes nicely to whipped cream or vanilla ice cream. It is best to have rather firm cooking apples so the slices will stay whole. New Cortlands, Rome Beauty, or Golden Delicious are all fine.

The recipe is very detailed, because it was designed by Julia Child for young beginning cooks. It is from her book, ''From Julia Child's Kitchen'' (Knopf, $15 ).

If there is a young cook nearby, ask if he or she would like to make this for a warm fall dessert to celebrate the start of the apple season. Pommes Rosemarie About 4 pounds (12 medium) cooking apples, such as new Cortlands, Rome Beauty, Golden Delicious 1 lemon 1/2 to 3/4 cup sugar, depending on sourness of apples 1 teaspoon cinnamon 1/2 teaspoon mace or cardamom 2 cups lightly pressed down fresh white bread crumbs 4 ounces (1 stick) butter

One at a time, with a small sharp knife, cut apples in half lengthwise, through stem end, then cut the half in half. Dig out the bit of core in the center of each quarter with your knife, then shave off the peel.

Cut apple quarters into 3 or 4 lengthwise slices - I find the fastest way to do this is to hold the apple piece with its curved side down on the cutting board, and then slice. Drop each slice into large mixing bowl.

When all apples are sliced, grate zest (colored part of peel only) of the lemon over the apples, and squeeze in the juice. Sprinkle on the sugar, cinnamon , and mace or cardamom. Toss apples to coat them. Taste, and sprinkle on more sugar if too sour.

Adjust oven rack to lower-middle level and turn oven on to 425 degrees F. Prepare bread crumbs, first by slicing crust off bread - you will need about a third of a 1-pound loaf to make 2 cups of crumbs.

Either rub bread against large holes of grater, or tear into smallish pieces and whirl a handful at a time in electric blender. Then cut butter into eighths for quick melting, and set it in saucepan over moderate heat until bubbling; stir in crumbs.

Spread one fourth of buttered crumbs in bottom of a 2 1/2- to 3-quart baking dish about 3 inches deep, with cover. Cover with half the apple slices, and spread over them half the remaining crumbs.

Spread on rest of apples, pour on any juices, and cover with last of crumbs. Lay a piece of buttered aluminum foil, butter side down over dish, and set on cover.

Bake for 30 to 40 minutes, until juices have bubbled over crumbs on top. Then uncover and let apples cook until juices are thick and syrupy when you tip dish, about 30 minutes more. Serves 6.