A few weeks ago, I received a request from Nina, a reader who loves Okinawan sweet-potato pie. She wanted to make the pie, and had checked recipes on the Internet, but "everything calls for a lot of butter, cream and whole milk, etc."

I, too, enjoy the purple potato pie with the flavors of the buttery shortbread crust, the custardy sweet potato and the creamy haupia on top. But, auwe! We have the problem of the high fat and sugar. It is so easy to cook with plenty of butter and sugar, but more of a challenge to go the other way.

I have never made this pie before, so I got on the phone with two of my cooking buddies. Lynne and Jenny offered some suggestions for substitute ingredients.

First, I tried a lower-fat pie with a Grape Nuts cereal crust and baked filling. My workout friends liked it and no one said they missed the butter and the sugar. In fact, they loved this pie more than the original recipe.

Then Jenny and I tried a version with a Vanilla Wafer crust and no-bake filling. It was great, but not as healthful.

I'm sharing both with you today.

To get a beautiful rich purple color, select Okinawan sweet potatoes that are fresh and firm.

This pie is fairly simple to make. You can start the sweet potatoes steaming and make the crust while they cook. Make sure you completely cool the crust before adding the filling, otherwise you will have a soggy layer.

For the final presentation, you could sprinkle a few slivered almonds on the top and add a sprig of mint and a purple orchid. It looks so beautiful, and tastes so 'ono, people will be asking you to bake one for them. I have already received several orders.

OKINAWAN SWEET POTATO PIE I

For the crust:

1 cup Grape Nuts cereal

2 tablespoons Splenda or other sweetener

1/8 teaspoon almond extract

3 tablespoons egg substitute

Non-fat cooking spray

For the filling:

1 tablespoon Smart Beat (low-fat margarine)

1/2 cup Splenda

1/2 cup egg substitute

1/2 cup non-fat evaporated milk

2 cups Okinawan sweet potato, peeled, cooked and mashed

1 teaspoon vanilla extract

1/2 teaspoon salt

1/2 TEASPOON CINNAMON

For the haupia:

1 cup Splenda

6 tablespoon cornstarch

2 cups (1 percent) milk

4 teaspoons coconut extract

Preheat oven to 350 degrees. Combine cereal, sweetener and almond extract in a small bowl and mix well. Stir in the egg substitute. Coat a 9-inch pie pan with nonstick cooking spray and use the back of the spoon to press the crust mixture across the bottom and sides of the pan to form an even crust. Bake at 350 degrees for 12-14 minutes or until the edges are lightly browned. Set aside to cool.

In a bowl, beat the Smart Beat margarine and Splenda until lightened and smooth-textured. Add egg substitute and non-fat evaporated milk; mix. Add mashed sweet potato, vanilla, salt and cinnamon; mix well. Pour into baked crust and bake for 40 minutes. Cool completely before adding the haupia topping.

To make haupia topping, in a medium mixing bowl, thoroughly mix the Splenda, cornstarch, milk and coconut extract. Place in a medium saucepan and stir constantly until the mixture thickens. Pour this mixture over the sweet potato filling and chill long enough to cool the haupia.

Serves 8.