Strawberry Shortcakes with Vanilla-Orange Syrup

Preparation

1. Make cake:

   Step 1

   Preheat oven to 350°F and butter an 8- by 2-inch square metal baking pan. Line bottom of pan with parchment or wax paper, then butter paper. Dust with flour, knocking out excess.

   Step 2

   Whisk together yolks, 1/2 cup sugar, milk, and vanilla in a large bowl until combined well. Whisk in flour and salt (batter will be thick).

   Step 3

   Beat whites with an electric mixer until they hold soft peaks. Gradually beat in remaining 1/4 cup sugar and beat until whites hold stiff, glossy peaks.

   Step 4

   Stir about one third of whites into batter to lighten, then fold in remaining whites in 2 more batches, gently but thoroughly.

   Step 5

   Transfer batter to baking pan, spreading evenly, and bake in middle of oven until pale golden and a tester comes out clean, 14 to 16 minutes. Cool cake completely in pan on a rack (cake will shrink from sides of pan). When cool, run a sharp knife around side of cake if necessary and invert onto rack, then remove paper.

2. Make strawberries in syrup:

   Step 6

   Scrape seeds from vanilla bean with tip of sharp knife into a small saucepan, then add pod. Add sugar, water, zest, and juice. Bring to a boil, stirring until sugar is dissolved, and boil 1 minute.

   Step 7

   Transfer to a bowl and chill 30 minutes. Pour syrup through a fine sieve into another bowl and discard solids. Gently stir in strawberries and let stand 15 minutes.

3. Make cream:

   Step 8

   Beat together cream, sugar, and sour cream until mixture just holds stiff peaks.

4. Assemble shortcakes:

   Step 9

   Cut 4 rounds from cake with cookie cutter.

   Step 10

   Generously brush both sides of each round with syrup from strawberry mixture and arrange, darker sides up, on plates. Spoon strawberries onto rounds and let stand 5 minutes to allow more syrup to soak into cake. Top rounds with dollops of cream and drizzle with remaining syrup.