Raspberry-Hibiscus Poke Cake

This recipe puts a modern spin on the retro poke cake, a popular 1970s dessert made by poking holes in a sheet cake and pouring in bright Jell-O for a moist, groovy-looking crumb. In this case the gelatin mixture gets its fruit flavor and color from a combination of hibiscus and fresh raspberries, a take on Celestial Seasonings Red Zinger tea. The whole thing is topped off with a marshmallow whipped cream frosting. Chopsticks are the ideal size for poking the holes in the cake, but the slender handle of a wooden spoon or fork will also work. —BA Test Kitchen
Recipe information
Yield
12 Servings
Ingredients
Cake
filling
topping and assembly
Preparation
Cake
Step 1
Place a rack in middle of oven; preheat to 325°. Butter a 13x9" baking dish. Whisk flour, baking powder, baking soda, and salt in a medium bowl to combine.
Step 2
Using an electric mixer on medium-high speed, beat sugar and remaining 1 cup butter in a large bowl until light and fluffy, about 4 minutes. Add egg whites, one at a time, beating to blend after each addition and scraping down sides and bottom of bowl occasionally, until very light and airy, about 3 minutes. Beat in lemon zest, vanilla extract, and almond extract.
Step 3
Reduce mixer speed to low, add dry ingredients in 3 additions, alternating with buttermilk in 2 additions, starting and ending with dry ingredients. Increase speed to medium-high; beat 2 minutes. Scrape batter into prepared pan and smooth out evenly to edges.
Step 4
Bake cake until golden brown and a tester inserted into center comes out clean, 45–55 minutes. Transfer pan to a wire rack and let cake cool in pan 15 minutes.
filling
Step 5
While the cake is cooling, place raspberries in a fine-mesh sieve set over a medium bowl. Using a wooden spoon, press down on raspberries until you have 1 cup juice; discard solids (or save for another use). Sprinkle gelatin over; let sit 10 minutes.
Step 6
Meanwhile, stir sugar, hibiscus flowers, and 1½ cups boiling water in a small bowl to combine and let sit 10 minutes. Strain through a fine-mesh sieve into bowl with raspberry mixture; discard solids. Whisk until filling is smooth.
Step 7
Using a chopstick, poke holes down into cake at 1" intervals. Slowly pour filling over cake, letting it seep into holes. Chill cake while you make the topping to let the filling set up a bit.
topping and assembly
Step 8
Heat marshmallows, vanilla extract, and ½ cup cream in a medium saucepan over medium, stirring constantly, until marshmallows are melted, about 3 minutes; chill remaining 1 cup cream until ready to use. Let marshmallow cream cool, about 30 minutes.
Step 9
Using an electric mixer on medium-high speed, beat chilled 1 cup cream in a large bowl until soft peaks form. Scrape in marshmallow cream and beat until almost stiff.
Step 10
Turn cake out onto a platter. Turn right side up and spoon marshmallow whipped cream on top. Spread to edges, making dips and swirls.
Do ahead: Cake (without topping) can be made 2 days ahead. Wrap tightly and chill.