Ingredients
Method
Make the Passionfruit Curd
- In a small saucepan set over medium high heat, bring the passionfruit nectar to a boil. Once boiling, turn the temperature down to medium low and simmer until the nectar has reduced to ⅓ cup. This will take around 30-40 minutes. Let the reduced nectar come to room temperature before using in the curd.
- Fill the bottom pan in a double boiler with 1-2 inches of water. Bring the water to a boil over high heat, then reduce the heat to low and bring the water to a simmer.
- In the top pan of the double boiler, whisk together the egg yolks, sugar, ⅓ cup reduced passionfruit nectar, and salt. Place on top of the simmering water and cook, whisking constantly, for 10 minutes. The curd should lighten in color and thicken as it cooks. To be precise, the curd should read around 160℉ on an instant read thermometer. Remove the top pan from the simmering water and whisk in the butter. The heat from the curd should be enough to melt the butter. Once the butter is completely melted, pour the curd into a glass jar or bowl and place a piece of cling wrap on top so that it's touching the surface of the curd. Chill the curd for 2 hours while we make the cupcakes.
Make the cupcakes
- Preheat the oven to 350℉. Line a 12 count muffin tin with cupcake liners and set aside.
- In a large mixing bowl using either a hand or a stand mixer fitted with a paddle attachment, beat the butter and granulated sugar together on medium speed until fluffy and combined. Add the eggs and vanilla and beat until combined. It may look a little curdled, that's ok!
- In a smaller bowl, whisk together the flour, baking powder, and salt. Add the dry ingredients to the wet ingredients, along with the lemon zest, and mix on low speed until almost combined. With the mixer still running on low speed, slowly stream in the whole milk and lemon juice. The batter may look a tiny bit curdled, this is just because of the lemon and won't be a problem once you bake the cupcakes.
- Fill the liners ⅔ of the way full. Bake for 18-20 minutes or until the cupcakes bounce back when lightly poked, and an inserted toothpick comes out clean. Let the cupcakes cool completely in the tin set over a wire cooling rack.
Fill the cupcakes
- Once the cupcakes are completely cooled, fill them with the passionfruit curd. Watch the video in the above blog post to get a visual on how this process works. Using a sharp knife, cut a circle into the center of the cooled cupcakes to create a pocket a little over 1 inch deep. The piece you remove will be cone shaped, so cut off the pointed end but keep the round "hat". Spoon a loaded teaspoon of the curd into the hole to fill to the top, and top with the round part you cut out to seal the hole. Repeat with the remaining cupcakes.
Make the frosting
- In a large mixing bowl using either a hand or stand mixer fitted with a whisk attachment, whip the butter and shortening on high speed for 4 minutes. It should be creamy and lightened in color. Add the confectioners sugar, blackberry jam, vanilla, and salt and mix on low speed for 30 seconds until combined, then turn the speed up to medium high and whip for around 1 minute. The frosting should be thick and creamy.
- Fill a large piping bag fitted with a star tip (I used Wilton 1M) with the frosting. Pipe the frosting in a swirl on top of the cupcakes.
- Cupcakes keep for up to 4 days sealed in an airtight container in the refrigerator.