Blueberry Curd

• • Chop the butter into about 5 pats of butter. Place it in a large non-metal bowl. . Set a sieve over the bowl. Set aside.
  • In a medium sized heavy bottom saucepan, combine the sugar and lemon zest. Rub the zest into the sugar with your fingertips. Rubbing the zest into the sugar is optional. It will help release the oils of the zest and enhance the lemon flavor.
  • Add the egg, egg yolk, and salt to the saucepan and whisk with a silicone whisk til smooth.

• Stir in the blueberries and lemon juice. Stir constantly with a rubber spatula or silicone whisk over medium-low heat til mixture comes to a simmer then thickens enough to coat the back of a spoon, should take around 10 minutes.
• Strain the curd through the sieve, pushing it through the sieve with a spatula to Discard the blueberry skins.
• Stir in the cold, chopped butter til melted. Gently press a piece of plastic wrap directly on the surface of the curd. Set the bowl in the refrigerator to cool and thicken for at least 2 hours.

Lemon Cupcakes

• Preheat oven to 350 F. Line muffin pan with paper liners. 
• In a medium bowl, whisk to combine the rest of the flour, baking powder, baking soda and salt. Set aside.
• In a standing mixer fitted with the paddle attachment or in a large bowl using a hand held mixer beat the butter, sugar and lemon zest on medium-high speed for 3-4 minutes until fluffy and well combined.
• Mix in the eggs one at a time. Scrape down the sides of the bowl. Mix in the vanilla extract. 
• In a small bowl, stir to combine the milk and lemon juice.
• Mix in the dry ingredients and milk-lemon mixutre in alternating batches, starting and ending with the flour. Mix only until just combined.
• Use a 1/4 cup measure or an ice cream scoop to scoop the batter and evenly fill the liners 2/3 to 3/4 of the way full. You might have a little extra batter leftover, just discard it. Don’t overfill the muffin pan.
• Bake for 17-21 minutes, until a toothpick comes out clean when inserted into the center. Remove from oven. Cool cupcakes in tin for ten minutes then remove and transfer them to a cooling rack. Cool completely before filling and frosting. 

Lemon Cream Cheese Frosting

• In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and the cream cheese on medium speed until combined.
• Turn the mixer to low and add the powdered sugar, ½tablespoon of the blueberry curd (milk or cream), lemon zest, vanilla extract and salt.
• Beat 2-3 minutes or until light and fluffy. If the frosting is too thick, add up to a little more blueberry curd or milk until desired consistency. If it’s too thin, add more powdered sugar.

Assembling and Decorating

• Use a cupcake corer (or the wide end of a large piping tip) to carve out a hole in the cupcakes. Remove the center of each cupcake. Discard centers (or save them for snacks!)
• Spoon or pipe at least 1 teaspoon of blueberry curd into the middle of each cupcake.
• Pipe or frost the cupcakes as you like. I used a Wilton 6B tip to frost mine. For the easiest and prettiest decoration, pipe one circle around the opening of the cupcake so that the curd filling in the middle is visible.