In a large bowl, beat the potatoes, cream, egg yolks, lemon juice, lemon peel and spices until smooth. Fold in ⅔ cup coconut.
In a large bowl with clean beaters, beat egg whites on medium speed until soft peaks form. Gradually beat in brown sugar, 1 tablespoon at a time, on high until stiff glossy peaks form and sugar is dissolved.
With a spatula, stir a fourth of the egg whites into sweet potato mixture until no white streaks remain. Fold in remaining egg whites until combined.
Transfer to a greased 11-by-7-inch baking dish. Sprinkle with almonds and remaining coconut. Bake at 325 degrees for 50–55 minutes or until a knife inserted near the center comes out clean. Serve warm with ice cream if desired.