Thai Tea Layer Cake

Ingredients

For The Thai Tea Concentrate

• 6 Tablespoons (1.35 ounces or 38 grams) Thai tea leaves
• 1 1/2 cups (12 ounces or 240 grams) boiling hot water

For The Thai Tea Cake

• 3 cups (12 ounces or 340 grams) cake flour
• 2 cups (14 ounces or 397 grams) granulated sugar
• 4 1/2 teaspoons baking powder
• 1 teaspoon kosher salt
• 1 cup (2 sticks or 8 ounces or 227 grams) unsalted butter, at room temperature
• 1 cup (8 ounces or 227 grams) Thai tea concentrate, at room temperature
• 5 large egg whites, at room temperature
• 1/3 cup (2.65 ounces or 75 grams) whole milk, at room temperature
• 1/2 teaspoon pure vanilla extract

For The Sweetened Condensed Milk Frosting

• 1 1/2 cups (3 sticks or 12 ounces or 340 grams) unsalted butter, at room temperature
• 1/2 teaspoon pure vanilla extract
• 1/4 teaspoon kosher salt
• 4 1/2 cups (18 ounces or 510 grams) confectioners’ sugar, sifted if necessary
• 3 Tablespoons (1.5 ounces or 43 grams) sweetened condensed milk
• 3Tablespoons (1.5 ounces or 43 grams) Thai tea concentrate, at room temperature
• 1/4 teaspoon orange food coloring

Equipment

• fine-mesh sieve
• 2 (8-inch) cake pans with at least 2-inch high sides

Instructions 

1. First, make the Thai tea concentrate. In a medium bowl, whisk together the Thai tea and boiling water. Let steep for 5 minutes. Place a fine-mesh sieve over a large liquid measuring cup. Strain out the tea leaves by pouring the concentrate through the sieve into the measuring cup, using a rubber spatula to gently press the leaves against the sieve to strain them further. You should have around 1 ½ cups Thai tea concentrate. Cool to room temperature before using in the cake batter and frosting recipes.
2. Prep the oven and pans to make the Thai tea cake. Position a rack in the center of the oven and preheat the oven to 350°F.Generously spray two 8-inch round cake pans with cooking spray and line the bottom of each with a parchment paper circle. Spray the parchment, too.
3. Make the cake batter. In the bowl of a stand mixer fitted with the paddle attachment, combine the flour, sugar, baking powder, and salt for the cake. Beat on low until just combined about 15 seconds. Add the butter for the cake all at once and beat on low until the mixture has the texture of coarse meal, with pea-sized pieces of butter throughout, about 3 minutes. Add the Thai tea for the cake and increase the mixer speed to medium. Beat until the batter is light and fluffy, about 2 minutes, using a rubber spatula to scrape down the bottom and sides of the bowl as necessary. While the batter is mixing, whisk together the egg whites, milk, and vanilla for the cake in a large liquid measuring cup. Reduce the mixer to low and add the egg white mixture in three additions, scraping down the bottom and sides of the bowl after each addition, then beat until just combined.
4. Assemble the cake layers. Divide the batter evenly between the pans; if using a digital scale to measure out the layers, note that this recipe makes around 50 ounces (1417 grams) of batter. Pour 25 ounces (709 grams) of batter into each pan.
5. Bake the cakes. Bake for 40 minutes. When done, the top of the cake should bounce back when gently pressed and a skewer inserted into the center of the cake should come out with a few crumbs attached.Cool completely in the pans on a wire rack before frosting.
6. Make the sweetened condensed milk frosting. In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, vanilla, and salt for the frosting on medium-low until smooth and creamy, about 1 minute. Reduce the mixer to low and add the confectioners’ sugar 1 cup at a time, beating until combined. Scrape down the bottom and sides of the bowl with a rubber spatula. In a small liquid measuring cup, whisk together the sweetened condensed milk, Thai tea, and orange food coloring. With the mixer on low, slowly pour in the mixture and beat until just combined. Scrape down the bottom and sides of the bowl once more, then beat on medium-high until the frosting is creamy and smooth, 2 to 3 minutes.Use immediately.
7. Assemble the cake. If necessary, level the top of both cakes. Place one of the cake layers on a cake board or serving platter in the center of a rotating cake stand. Use a rubber spatula or cookie dough scoop to drop ½ cup of frosting in the middle of this cake layer. Spread it evenly all over the top, just like you would spread butter on toast. Place the second cake on top of this frosting, stacking it evenly on top of the first cake.
8. Crumb coat the cake. Cover the surface of the entire layer cake with a thin layer of frosting. Use just enough frosting to cover the entire cake completely. Refrigerate, uncovered, for 30 minutes to stiffen and “set” the frosting.
9. After the crumb coat sets, finish frosting the cake. Cover the cake completely with the remaining frosting, using an offset spatula to spread the frosting all over the top and sides of the cake evenly. 
10. Serve and store. Serve immediately. The assembled cake can be stored at room temperature, under a cake dome or a large bowl turned upside down, for up to 1 day. Press a sheet of plastic wrap against any cut surfaces to prevent the cake from drying out. After that, cover the entire cake loosely with plastic wrap and refrigerate for up to 2 days.