Mini Baked Alaskas

Preparation

1. Cake

   Step 1

   Place a rack in middle of oven and preheat to 350°. Butter a rimmed 18x13" baking sheet or lightly coat with nonstick spray. Line with parchment paper; lightly butter or coat parchment and dust lightly with flour, tapping out excess. Whisk together eggs, egg yolk, buttermilk, coffee, oil, and vanilla extract in a medium bowl.

   Step 2

   Mix granulated sugar, cocoa powder, salt, baking soda, baking powder, and 1¾ cups (219 g) flour in the bowl of a stand mixer fitted with paddle attachment on low speed until combined, about 1 minute. Add egg mixture in 3 additions, beating on medium speed 30 seconds after each addition. Add melted chocolate and beat, scraping down sides of bowl to ensure everything is well mixed.

   Step 3

   Scrape batter into prepared baking sheet and rap on counter to level. Bake cake until a tester inserted into the center comes out clean, 20–25 minutes. Let cake cool 15 minutes, then run an offset spatula along edges to loosen. Set a wire rack upside down over baking sheet and flip over to release cake. Carefully peel away parchment paper and let cool completely.

2. Meringue and Assembly

   Step 4

   Transfer cake to a cutting board. Cut out 12 rounds with cookie cutter (leftover scraps are for snacking). Top 6 cake rounds with a 1 Tbsp. dollop of jam each; sandwich with remaining cake rounds. Place each cake sandwich on an 8" square of plastic wrap (lightly moistening the counter will help plastic stay flat).

   Step 5

   Soften ice cream just enough to be able to scoop with a #8 ice cream scoop (or a heaping ½ cup). Arrange a scoop of ice cream, flat side down, on top of each cake sandwich. Pull plastic wrap up and around cake and ice cream and twist to seal tightly. Freeze until ice cream is very hard, at least 1 hour.

   Step 6

   Just before serving, heat egg whites, granulated sugar, and cream of tartar in the bowl of a stand mixer set over a saucepan of barely simmering water (do not let bowl touch water), whisking constantly, until sugar is dissolved and an instant-read thermometer registers 120°, 5–7 minutes.

   Step 7

   Fit bowl onto stand mixer fitted with whisk attachment, add vanilla extract, and beat on medium-high speed until meringue forms stiff, glossy peaks, about 5 minutes.

   Step 8

   Unwrap ice cream domes and place on individual heatproof plates. Working quickly, spread meringue over domes with a spoon or small offset spatula, making lots of decorative swirls and peaks all over. (You can also use a pastry bag fitted with a large fluted tip and pipe meringue over each dome.) Make sure all of the ice cream and cake is covered. Toast meringue with kitchen torch until golden.

   Do Ahead: Ice cream domes can be assembled 3 days ahead. Keep frozen. Cover with meringue and toast just before serving.