Preheat oven to temperature suggested on the cake box. Grease and flour three (3) 9-inch cake pans.
Prepare the cake mix using the egg whites, coconut milk ,and water instead of the ingredients called for on the cake mix box. Pour the batter into the three (3) prepared cake pans.
Bake for approximately 18 minutes. The cake is done when the sides shrink back slightly from the side of the pan, and when the top springs back when lightly pressed with fingertips, or when a cake tester or toothpick inserted in the center of the cake comes out clean. Remove from oven and let cool on wire racks for 10 minutes. After 10 minutes, remove the cake pans and place on wire cooling racks.
Prepare Haupia Filling (see recipe below).
Assemble Cake: Put one of the cake layers on a cake plate so that the bottom of the cake (flat side) is on top. Place strips of waxed paper around the bottom of the cake layer to protect the cake plate from spills and keep it clean. Spread just under 1/2 the Haupia Filling on top of the layer. Place the cake dish in the refrigerator for approximately 15 minutes to firm up the filling.
After the 15 minutes, remove the cake plate from the refrigerator and place the 2nd layer of cake on top, again so the bottom of the cake (flat side) is on top. Spread most of the remaining 1/2 of the Haupia Filling on top of the 2nd layer. Then place the last (3rd) layer, rounded side up, on top of the filling. Use the last bit of filling to smooth between any gaps in the layers along the sides of the cake. Place the cake back in the refrigerator for at least 30 minutes before frosting.
Prepare Whipped Cream Topping (see recipe below).
Using a metal spatula, spread the prepared Whipped Cream Topping over the top and sides of the cake. Sprinkle the flaked or shredded coconut over the top. Carefully remove the pieces of waxed paper.
Refrigerate cake until ready to serve.
Makes one (1) large cake.
In a small bowl, combine the cornstarch and water; set aside and let sit for a few minutes.
In a large saucepan over low heat (cook over low heat to avoid curdling), add the coconut milk, sugar, and salt, stirring to dissolve the sugar. When the sugar is dissolved, add the cornstarch/water mixture. Stirring constantly, bring to a boil. NOTE: If you do not stir constantly, the mixture will burn at the bottom of the pan. Let boil, stirring constantly, for approximately 1 minutes or until the Haupia becomes thick. Remove from the stove and stir every few minutes as the mixture cools. After about 10 minutes, stir in the vanilla extract and allow to cool. NOTE: It is best to refrigerate the haupia until it is somewhat thick, but still spreadable; otherwise it can goop up when you try to spread it on the layers.
In the bowl of your electric mixer, beat the cream until it is slightly thickened. Add the powdered sugar and vanilla extract; beat until the cream is whipped and forms peaks.
* Use only thawed frozen coconut milk - not canned coconut milk, cream of coconut, or coconut juice. Coconut milk can be found in plastic 12-ounce or 16-ounce pouches or in 12-ounce frozen cans in the freezer section of most Asian supermarkets.
Haupia Cake - Hawaiian Pudding Cake Recipe: https://whatscookingamerica.net/cake/haupiacake.htm