Preheat oven to 325°F. Beat egg whites (at room temperature) at high speed of an electric mixer until foamy.
Gradually add ½ cup sugar, 2 tablespoons at a time, beating until stiff peaks form.* Fold in baking powder, pecans and vanilla (Original recipe also included ⅔ cup saltine cracker crumbs.)
Spoon meringue mixture into a buttered 9-inch pie plate. Bake for 30 minutes. Let cool. Meanwhile, beat whipping cream at high speed until foamy; gradually add 2 tablespoons sugar, beating until soft peaks form.
Fold in sliced strawberries and spoon evenly over meringue crust. Chill pie until ready to serve.
*At higher altitudes, egg mixtures whipped to the maximum will collapse as the lower air pressure encourages the air cells to keep expanding. To account for this, whip the eggs a little less—to soft peaks instead of stiff ones for egg whites—to allow for expansion.
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Notes
Original recipe also included ⅔ cup saltine cracker crumbs folded into the meringue before baking. I've also tried this recipe with Splenda sweetened cream instead of sugar and it turns out nicely.