Caramel Apple Cake

A luxurious 3-layer cake of fresh apples and caramel. Makes 8" four-layer cake (can be four layers if desired). Adapted from Layered by Tessa Huff (cake) and Erin McDowell (buttercream).

Course: Dessert

Keyword: Cake

Author: hello kelinda

Equipment

2 8" cake pans

Materials

Apple Cake

2 1/2 cups all-purpose flour (315 g)
2 tsp baking powder
1/2 tsp baking soda
1/2 tsp salt
1/2 tsp ground cinnamon
1/4 tsp ground cardamom
1/2 cup + 2 tbs grapeseed oil (150 ml)
1 1/4 cups sugar (250 g)
2 tsp lemon zest
2 large eggs + 1 yolk
1/2 cup buttermilk (120 ml)
1 3/4 cups finely diced and peeled apples, preferably Granny Smith or Honeycrisp (280 g)

Italian Buttercream

5 large egg whites (180 g)
1/4 tsp cream of tartar
1 3/4 cups sugar (350 g)
3/4 cups water
2 cups unsalted butter, room temperature and cut into tablespoons
1 1/2 tsp vanilla extract
1/2 tsp fine sea salt

Honey Sour Cream Buttercream

2 1/2 cups Italian meringue buttercream (see above)
2/3 cup sour cream (160 ml)
2 tbs honey
1/4 tsp ground cardamom

Apple Cider Caramel

1 cup apple cider (240 ml)
1/2 cup light brown sugar (110 g)
1 tsp light corn syrup
2 tbs unsalted butter, cold and cut into cubes

Instructions

Make the Apple Cake

Preheat the oven to 350°F. Grease and line the bottom of two 8" cake pans with parchment.
Sift the flour, baking powder, baking soda, salt, cinnamon, and cardamom together in a bowl and set aside.
Beat together the oil, sugar, and lemon zest with the paddle attachment for about 2 minutes.
Lower the mixer speed to medium-low and add in the eggs and egg yolk one at a time. Scrape down the bowl.
Lower the speed again to low and add the flour mixture in three batches, alternating with the buttermilk — begin and end with the flour mixture.
After the last of the flour disappears into the batter, bump up the speed to medium and beat for 30 seconds. Don't overmix!
Fold in the diced apples.
Divide evenly between the cake pans and bake for about 20-30 minutes, or until the top looks golden and a cake tester comes out clean. However, because of the fresh apples, probe in a few places near the center of the cake if your tester comes out wet just in case you happened to spear an apple chunk.
Let the cake cool on a wire rack in its pan for 15 minutes before turning it out to cool completely directly on the rack.

Make the Italian Buttercream

Put egg whites and cream of tartar into the bowl of a stand mixer fitted with a whisk attachment.
In a medium pot, bring the water and sugar to a boil. Stir until the sugar is dissolved, then let it boil untouched until it reaches 230°F. At this point, turn the stand mixer on at medium-high to whip the egg whites.
When the sugar syrup mixture reaches 240°F — which should only be a few more minutes — take it off the heat. Kick the mixer up to high and slowly stream the syrup into your running mixer.
Let the mixer keep running once all the syrup has been added until there’s no more heat escaping out of the top and the mixer bowl feels barely warm. This usually takes my mixer about half an hour. Yes, it’ll be loud.
Once the bowl has cooled and your meringue is holding glossy stiff peaks, add the butter in one tablespoon at a time, allowing each addition to incorporate into the meringue before adding the next.
When all the butter has been added and incorporated, add the vanilla extract and salt. Beat for another minute to fully incorporate.
Your buttercream is now ready for use. Set aside 2 1/2 cups of it for the filling and reserve the rest for piping the dam and frosting the outside of the cake.
NOTE: If your mixture looks soupy during the butter-adding stage, pop it into the fridge for a few minutes before resuming the process.

Make the Honey Sour Cream Buttercream

Beat the 2 1/2 cups of buttercream with the sour cream, honey, and cardamom in a stand mixer fitted with a paddle attachment until it's all smooth and uniform.

Make the Apple Cider Caramel

Place the apple cider in a deep medium saucepan and simmer it until it reduces to 1/4 cup.
Once your cider has reduced, add the brown sugar and corn syrup to the saucepan. Plonk a candy thermometer into the saucepan and raise the heat until it boils — it will bubble like crazy at first and then calm a bit.
Boil until it reaches 240°F. Remove it from the heat and stir in the butter.
Store in an airtight container and let it cool. Use while it's still a touch warm. If you make it ahead of time, warm it gently in a warm water bath until it's viscous again.

ASSEMBLY

Slice each cake in two to form two layers. It's up to you whether to keep the last layer for yourself (yielding a three-layer cake) or for the cake (yielding a four-layer cake). A three-layer cake will have more buttercream to cover the outside, whereas a four-layer cake will have a thinner outer buttercream coat. Both are delicious.
Place one layer on your cake board.
Pipe a dam of the reserve buttercream around the perimeter of the cake slice. This will keep your filling from oozing out.
Spread a layer of the honey sour cream buttercream inside the dam, using as much as to match the height of the dam.
Stack with the next slice of cake.
Repeat steps 3-5 for the remaining layers except the last.
Frost the outside of the cake with the remaining reserve buttercream.
Spread a generous layer of the apple cider caramel over the top, letting it run down the sides.
Decorate as you like! I topped mine with small caramel apples.

Notes

Serving: Because the interior buttercream contains sour cream, it’s best to keep this cake refrigerated. However, leave it out at room temperature for about an hour beforehand to let the cake and frosting soften. Enjoy!

Do ahead: Baked and cooled cakes can be wrapped tightly in clingfilm and frozen ahead of time. Thaw overnight in the fridge before assembly. Apple cider caramel can be made 2 days ahead of time and stored in an airtight container. Gently warm in a bowl of warm water to loosen it again for assembly.