In a small sauce pan, heat the butter on medium-high heat until it browns and begins to smell like toffee. Do not burn it. Set the butter in the freezer to cool until safe enough to handle.
In a medium mixing bowl, lightly whisk together the milk, egg yolks, and vanilla extract. Set the liquid aside.
In a large mixing bowl, whisk together the flour, sugar, baking powder, salt, cinnamon, and cardamom. Beat the browned butter into the flour mixture until just combined.
A third at a time, beat in the egg mixture into the flour and butter mixture. Blend until combined, then beat the mixture for an additional 30 seconds. Do not overmix the cake.
Line a muffin tray with 12 cupcake liners. Fill each liner with batter 2/3 of the way.
Bake the cupcakes for 25 to 30 minutes or until cupcakes are golden brown and a toothpick runs clean when probed into the cake. Brush the top of each cake with a light layer of simple syrup or honey while it is hot to keep the cake moist as it cools.
Set the cupcakes aside to cool completely.
Poke a hole into each cupcake with the end of a spoon or your thumb and, using a pastry bag or Ziploc bag with a corner cut out, fill each cupcake with apple jam.
Make the Buttercream
In a double boiler, heat the egg whites and sugar on medium heat, whisking them together continuously until the sugar is completely dissolved. The mixture should be gooey, shiny, and bubbly, and not look like scrambled eggs.
Place the egg mixture into a large mixing bowl, and using a hand mixer or stand mixer (preferred) with a whisk attachment, beat the sweetened egg whites until stiff peaks form. A shiny white meringue should form and the bowl should feel cool to the touch when finished. If the bowl is still warm, wait until it is cool before proceeding to the next step.
Half a stick at a time, add the softened butter to the meringue, mixing on low. When all of the butter has been incorporated, increase the speed to medium-high and add the vanilla extract. Scrape down the sides as needed. Beat the buttercream until it is white or nearly white in color. This can take between 5 to 10 minutes. The buttercream is finished when it is satiny smooth. Set aside.
Note: If making the buttercream ahead of time, place the buttercream in a freezer bag or plastic container and store in the refrigerator. Before using, let the buttercream come to room temperature and use your stand mixer and whisk attachment to whip the buttercream again until the consistency returns.
Make the Caramel
Combined the sugar and water in a small sauce pan or skillet and cook on medium heat. Using a pastry brush or a spoon filled with water, brush down the sugar crystals along the edges of the pan in order to prevent crystallization of the caramel. The caramel should turn from “wet sand” to golden brown syrup within 5 to 10 minutes. Do not stir it.
Add the butter and cook for another 3 to 5 minutes.
Slowly add the heavy cream and stir it in quickly. Once fully combined, cook for another 2 to 4 minutes until caramel forms. Remove it from the heat and set it aside to cool completely.
Make the Crumb Topping
In a medium bowl, mix together the toasted pecan pieces and toffee. Make sure the pecans are completely cooled.
Top the Cupcakes
Make sure all of the ingredients are completely cooled before proceeding.
Using a pastry bag and a plain ½ inch piping tip (if you don’t have a pastry bag and tip, simply use a spatula or ice cream scoop), frost each cupcake with the Swiss Meringue Buttercream or whichever frosting you chose to use.
Line the perimeter of each cupcake with the pecan-toffee crumb.
Finish each cupcake with a caramel drizzle.
To make simple syrup, simply dissolve ¼ cup of water and ¼ cup sugar on medium heat and set aside to cool. You will have extra syrup, so you can store the rest in the refrigerator. It stays for at least six months.
Feel free to make this a cake instead of cupcakes! Divide the cake batter into two 6” cake pans or 8” cake pans. Bake for 35 to 45 minutes or until cakes are golden brown and a toothpick runs clean when probed into the cake. Cut each cake in half, creating four layers. Fill each layer with apple jam. Frost the cake with buttercream, and line the edge of the cake with the pecan-toffee crumb. Drizzle with caramel. Enjoy!
If you don’t want to make the buttercream from scratch, you can use 4 Cups or 32oz (900g) of store-bought vanilla icing.
If you don’t want to make the caramel from scratch, you can use store bought caramel.