3 ¼cupscake flour or all-purpose flour,spooned and leveled
1 ½cupsgranulated sugar
3tspbaking powder
1tspcoarse Kosher salt(if using table salt, use half the amount)
1tspground cinnamon
1tspground ginger
½tspground cardamom
¼tspground allspice
¼tspground cloves
2large eggs
2large egg whites
¾cupwhole buttermilk,room temperature
½cupunsalted butter,melted
½cupvegetable oil
2tspvanilla extract
Buttercream
2cupsunsalted butter,softened to room temperature
4cupspowdered sugar
2tbspmeringue powder
¼tspcoarse Kosher salt(if using table salt, use half the amount)
2tspvanilla extract
6tbsphoney
¼cupBiscoff cookie butter
Instructions
Cake
Preheat the oven to 350 F, and spray the bottoms of three 8-inch cake pans with non-stick baking spray.
Warm the milk until very hot, almost boiling, then remove from the heat. Add the tea bags, let steep for 10 minutes, then throw away the tea bags.
Meanwhile, in a large bowl, sift together the flour, sugar, baking powder, salt and spices, then whisk until well combined.
In a separate bowl, whisk together the eggs, egg whites, buttermilk, melted butter, oil and vanilla, and whisk until smooth. Whisk in the warm chai tea milk.
Add the dry ingredients to the wet, and whisk until combined and smooth, about 10-15 seconds. Divide the batter between the cake pans. Tap a few times against the counter to pop any large air bubbles.
Bake the cakes for about 21-25 minutes, or until a cake tester or a toothpick comes out clean, and the tops spring back when lightly touched.
Set the pans on a cooling rack, cover them loosely with a clean kitchen towel, and cool completely before frosting. When ready to frost and assemble the cake, remove the cakes from the pans.
Buttercream
In the bowl of your stand mixer fitted with the whisk attachment, beat the butter for 1 minute until smooth.
With the mixer running on low, add the powdered sugar by spoonfuls, the meringue powder and the salt, mixing until thick and combined.
Add the vanilla, honey and cookie butter. Increase speed to medium and whip for 4-5 minutes, scraping the bowl down several times, until light and fluffy. Turn the speed down to low, and mix for 1 minute, to pop any large air bubbles.
Assembly
Remove the cooled cakes from the pans. If needed, use a sharp knife to level the tops of the cakes, if they're domed on top.
Stack and fill the cake layers with the buttercream, then frost all over with a thin crumb coat of buttercream.
Chill the cake for 45-60 minutes, until the crumb coat is cold and firm. Keep the remaining bowl of buttercream covered.
Fit a piping bag with tip 1M, and fill with buttercream. Starting at the bottom of the cake, move the piping bag from the bottom to the top, back to the bottom, in vertical rows of ruffles. Every few rows, stop at the bottom to turn the cake and adjust the piping bag, and continue piping ruffles all around the cake.