Preheat oven to 325°F and butter an 8 1/2- by 4 1/2- by 3-inch loaf pan. Put a 24- by 3 1/2-inch strip of wax paper lengthwise down center of pan (to facilitate unmolding), leaving an overhang on each end.
Whisk together cornmeal, flour, baking powder, and salt.
Finely grind almonds with 1/4 cup sugar in a food processor and stir into cornmeal mixture.
Beat butter and remaining 1/2 cup sugar in a large bowl with an electric mixer at medium speed until combined well. Beat in eggs 1 at a time until just blended, then beat in vanilla. (
Mixture will look curdled.)
Add cornmeal mixture and stir and fold until just combined.
Transfer batter to loaf pan, smoothing top, and bake in middle of oven until a tester comes out clean, about 1 hour. Cool cake in pan on a rack 5 minutes. Loosen edges with a knife, then use strips to carefully lift cake from pan onto rack.
