Chocolate Cupcake with Passion Fruit Curd

CHOCOLATE CUPCAKES
1/2 cup (113 g) unsalted butter, cut into pieces
2 oz (57 g) bittersweet chocolate, roughly chopped
1/2 cup (43 g) unsweetened cocoa powder
3/4 cup (94 g) all-purpose flour
1/2 teaspoon baking soda
3/4 teaspoon baking powder
2 large eggs
3/4 cup (150 g) sugar
1 teaspoon vanilla extract
1/2 teaspoon salt
1/2 cup (115 g) sour cream
PASSIONFRUIT CURD
1/2 cup passionfruit puree
1 cup (200 g) sugar
2 large eggs
2 large egg yolks
5 tablespoons (70 g) unsalted butter, room temperature, cut into 1-in pieces
FOR THE CUPCAKES:
Preheat oven to 350 degrees F. Line a 12 cup muffin pan with baking-cup liners.
Combine butter and chocolate in medium heatproof bowl. Set bowl over saucepan containing barely simmering water; heat mixture until butter and chocolate start to melt. Add cocoa and whisk until smooth and fully combined. Set aside to cool until just warm to touch.
Whisk flour, baking soda and baking powder in small bowl to combine

• Whisk eggs in second medium bowl to combine. Add sugar, vanilla and salt and whisk until fully incorporated.
• Add cooled chocolate mixture and whisk until combined.
• Sift about one-third of flour mixture over chocolate mixture and whisk until combined; whisk in sour cream until combined; then sift in remaining flour mixture and whisk batter until it is homogenous and thick.
• Divide batter evenly among muffin pan cups. Bake until skewer inserted into center of cupcakes comes out clean, 18-20 minutes. Cool cupcakes in muffin pan on wire rack until cool.

FOR THE CURD:

• Create a water bath by placing a saucepan of water over heat to simmer and placing a metal bowl unto the pan so its bottom does not touch the water. Whisk together passionfruit puree, sugar, eggs, and egg yolks in the bowl.
• Cook the mixture over the simmering water, whisking constantly, until the cream thickens and coats the back of a wooden spoon, about 6-8 minutes. Keep whisking while the mixture is heating up to prevent the eggs from cooking.
• Take mixture off heat. Add in butter a couple pieces at a time and stir to thoroughly melt and combine.
• Pour curd into a container and place a piece of plastic wrap against the surface. Cover and chill in refrigerator until ready to use.