Step 1

To make the cake: Preheat the oven to 325°F with a rack in the bottom third. Have on hand an ungreased 10" tube or angel food cake pan., In a large mixing bowl, beat the egg whites with the cream of tartar until foamy. Gradually add 1/2 cup (99g) of the sugar and continue beating until stiff and glossy. Set aside., In a medium bowl, whisk together the remaining 1 cup (198g) sugar with the flour, baking powder, and salt., In a large mixing bowl using a whisk attachment, beat the oil, reserved egg yolks, and extracts until pale yellow. Add the dry ingredients in thirds, alternating with the milk, beating at medium speed for 2 to 4 minutes., Gently fold in the whipped egg whites with a whisk or spatula just until the batter is uniform. Scrape the bottom of the bowl to ensure the batter is evenly mixed., Pour the batter into the prepared pan. Bake for 50 minutes without opening the oven; the cake will rise high above the pan then settle back almost even as it continues to bake., Increase the oven temperature to 350°F and bake for 10 minutes more, until a gentle touch on the center of the cake leaves no indent; if you listen carefully, the cake should make a crackling sound., Remove from the oven and invert the tube pan over the neck of a wine bottle for 30 minutes. After 30 minutes, use a thin-bladed flexible spatula to free the cake from the sides and tube of the pan. Turn the cake out onto a serving plate to finish cooling completely., To make the Chantilly cream: Place all the ingredients in a large, chilled mixing bowl. Beat until the mixture holds soft peaks., To serve: Sift confectioners' sugar over the cake, then slice. Top each slice with a spoonful of Chantilly cream or whipped cream; garnish with berries, if desired.

Step 2

, Storage information: Store leftover cake, well wrapped, at room temperature for several days; freeze for longer storage.