Preheat oven to 350 degrees and lightly oil 8-inch diameter cake pan.
Whisk flour, baking powder & salt in a medium bowl to blend.
Using an electric mixer, beat sugar, eggs & zests in a large bowl until pale and fluffy. Beat in milk, then gradually beat in oil.
Add the flour mixture and stir just until blended, then stir in almonds.
Transfer batter to pan and place on baking sheet to collect any spills. Bake until a tester inserted into center of cake comes out with moist crumbs attached, about 35 minutes.
Transfer to rack and cool for 15 minutes. Remove cake and place on serving platter, top side up. Sift powdered sugar over the cake.