Triple Lemon Cupcakes

Step 1
Preheat the oven to 350 degrees F (175 degrees C).

Step 2
Mix sugar, lemon juice, butter, eggs, and lemon zest for lemon curd filling thoroughly in a microwave-safe bowl. Microwave in 1-minute intervals, stirring between, until mixture is thick enough to coat the back of a metal spoon, usually about 7 minutes total. Let cool, about 10 minutes. Transfer to a zip-top bag and refrigerate until needed.

Step 3
Cream sugar and butter together for cupcakes in the bowl of a stand mixer until fluffy, about 10 minutes. Beat in eggs, 1 at a time, mixing vanilla and lemon extracts into the mixture with the last egg. Beat in flour, baking powder, and nutmeg until thoroughly combined; beat in buttermilk, lemon juice, and lemon zest to make a smooth batter.

Step 4
Fill each of the prepared cupcake cups with about 1/4 cup of batter, or use a large cookie scoop.

Step 5
Bake in the preheated oven until tops spring back when lightly pressed, 20 to 25 minutes. Cool in the tins for 5 minutes. Transfer to a wire rack to cool completely, about 20 minutes.

Step 6
Cream the cream cheese and butter for cream cheese frosting together in a medium bowl or stand mixer until creamy. Mix in lemon juice and lemon and vanilla extracts, then gradually stir in confectioners' sugar. Stir in lemon zest. Store in the refrigerator after use.

Step 7
Remove a section from the center of each cooled cupcake using an apple or cupcake corer. Cut off a corner of the zip-top bag holding the filling, and fill each cupcake with lemon curd. Pipe with a swirl of lemon cream cheese frosting, covering the curd filling. Refrigerate until ready to serve.