There's really very little disagreement among American eaters about the way apple pie ought to taste -- it ought to taste like the apple pie that mother used to make. That being the case, it's hard to understand why anyone's hand strays toward the commercial bakery pies in the supermarket frozen food case. Take a look at the ingredients list of a Mrs. Smith's Apple Pie, for example: "Apples, wheat flour, water, corn syrup, lard and/or beef fat, sugar, margarine (partialy hydrogenated soybean oil and/or non-fat dry milk, salt, lecithin, may contain mono-and diglycerides or citric acid/preservative, artificial color and flavor, vitamin A palmitate), brown sugar, modified food starch, salt, dextrose, spice, baking soda, sodium bisulfite." Does that sound like a mother's ingredients for apple pie?

I was accosted in a Virginia supermarket check-out line recently by a woman who spotted a factory pie in my basket, purchased as part of the research for this article.

"How could you buy a commercial apple pie?" she asked. "Apple pie baking is so simple. It's all in the apples and flaky crust, the less fuss the better."

Virginia apple pie bakers should know, especialy at this time of year as bushels of apples pile up in the orchards of the commonwealth and pies are baked by the dozen for every special occasion. Every Virginia cook seems to have a "best" apple pie.

Take 72-year-old Effie Jackson, the diminutive cook of the Virginia Byrd apple dynasty. Cook to the late senator Harry Byrd and now cook for his son, Bev Byrd, the present senator's brother, Jackson follows a system already practiced by some Virginia cooks in the 18th century. She begins a pie by simmering Stayman (or, if there's no choice, Delicious) apples with water and a little salt to "bring out their taste" before adding sugar and tapioca or flour. For 42 yars, as long as she has been cooking for the Byrd family, Jackson has been making apple pies the same way. For seasoning she insists on using either lemon or cinnamon, never both. "The two just don't go together." For Jackson, "good, pure lard makes the best crust but not the processed kind in supermarkets today. I use Crisco."

Once there were more than a thousand different varieties of apples from which to choose -- eating, baking, sauce-making apples, apples for every occasion. Most of them, alas, have disappeared. Insects, diseases, even blemishes like russet skins, natural spots or colors that did not store well, eliminated some varieties. Temperance workers cut down apple trees as they battled the evils of hard cider and applejack. (In this conection, bear in mind that to our pioneer forebears the apple was as much to drink as to eat; nearly every famiy consumed hundreds of gallons of the hard stuff and the harder stuff every year.)

And so, finally, arrived the misnamed Delicious apple. Most Americans eat only one apple today, the bland, beautiful Delicious. No less an authority than Harry Byrd III blames the ubiquity of Delicious apples on the growers of Washington state. "Their promotion of Red Delicious apples has taught housewives to buy on looks rather than taste. What we plant now has become dictated by what the consumer will buy. Black Twig, Loury and Smokehouse are all good apples which have been phased out." Byrd should know. He produces between 400,000 and 500,000 bushels in his orchards in Berryville, one-third of them Red Delicious, one-fifth of them York, and the balance Golden Delicious, Jonathan, Rome, Grimes, Stayman and York. He also has a few trees bearing the increasingly popular tart fruit of the Australian immigrant Granny Smith -- just enough for his own family, he says -- and one Ben Davis tree. Byrd recommends Staymans for pies.

An apple pie tasting was held recently at The Washington Post Magazine. Since every American is an apple pie authority, the Post Magazine staff members were good judges. Four different crusts and four different fillings were used, based on recipes drawn from Virginia apple pie bakeoffs, old cookbooks and new. All the judges could distinguish the apples used and the differing character of lard, butter and Crisco crusts. The tart Granny Smith apple, available at the time of the testing, easily topped the Golden Delicious rival, and the simplest oldest recipes took precedence over the modern, more doctored ones created perhaps to disguise tasteless apples.

Creation of the ultimate apple pie, we found, is a very simple matter. There are three essential components: a good short flaky crust, tart apples that hold their shape, and a subtle combination of sugar, spices and lemon. The apples should be hard and tart, not the bland Delicious or McIntosh. Use Stayman, Rome, Rhode Island Greening, Jonathan or that foreigner Grany Smith. Bite into the apple to determine how much sugar and spice to add.

There are two schools of thought on the eating of this ultimate apple pie. To some, this writer included, the apple pie does not improve on standing. Others, including her husband, prefer day-old pie. Day-old or hot from the oven, it should be eaten with vanilla ice cream or with a wedge of cheddar, for as any New England apple pie lover knows, "Apple pie without the cheese is like a kiss without a squeeze." ULTIMATE APPLE PIE Makes one nine-inch pie (Based on Miss Parloa's Kitchen Companion, 1888, and my mother) Crust: 1/3 cup unsalted butter 1/2 cup lard or Crisco 2 cups unsifted all-purpose flour 1/2 teaspoon salt 1/4 cup ice water Filling: 6-8 large peeled, cored tart apples, sliced in eighths 1/2 cup sugar or to taste 1/2 teaspoon cinnamon (optional) Dash of freshly grated nutmeg 1 tablespoon lemon juice according to tartness of apples 1/2 teaspoon grated lemon rind 1 tablespoon flour or tapioca 2 tablespoons water 2 tablespoons unsalted butter

Using two knives cut the butter and lard or Crisco with the flour and salt.

When crumbly add the water. Using the heel of the hand press small amounts of the dough away until well combined, working quickly. Place in a ball, wrap in wax paper and refrigerate.

Combine the apples, sugar, cinnamon, nutmet, lemon juice and rind, flour and water, Adjust seasonings.

Roll out little less than half the dough between two pieces of wax paper. Turn the dough into pie tin, and fill the pie with the apple sections, which should come way above the rim. Dot with butter.

Roll out the remaining dough. Using your fingers, moisten the rim of the bottom crust with cold water and lay on the top crust, crimping top to bottom. With a fork prick holes in the top.

Bake 15 minutes in an oven preheated to 450*, then bake about 30 minutes more at 350*, until the apples are soft but not mushy. Serve immediately or next day, but not the day after! APPLE PIE (From The Frugal Housewife, 1772 ) To make an apple or pear pie:

Make a good puf paste crust, lay some round the side of the dish. Pare and quarter your apples and take out the cores, lay a row of apples thick. Throw in half the sugar you design for your pie, mince a little lemon peel fine, throw over and squeeze a little lemon over them then a few cloves here and there one, then the rest of your apples and the rest of your sugar.

You must sweeten to your palate, and squeeze a little more lemon. Boil the peeling of the apples and cores in fair water, with a blade of mace, till it is very good. Strain it and boil the syrup with a little sugar till there is but very little and good, pour it into your pie, put on the upper crust and bake it. You may put in a little quince or marmalade if you please.