Preheat oven to 350 degrees F. Line 2 standard muffin tins with 16 foil cupcake liners; set aside.
Place shortbread cookie crumbs, sugar, and melted butter in a medium bowl; stir until well combined; set aside.
In the mixing bowl of an electric mixer fitted with the paddle attachment, beat cream cheese and sour cream until smooth. Add eggs 1 at a time and mix just until combined. Scrape down sides of the bowl. Add vegetable oil, water, and the box of lemon pudding. Mix until combined. Add cake mix and beat on medium speed for 2 to 3 minutes. Batter will be on the thick side.
Place a slightly heaping tablespoon of shortbread cookie crumb mixture into the bottom of each prepared muffin cup. Use your fingers or the bottom of a small glass to firmly pack crumbs into the bottom of each cupcake liner. Reserve remaining shortbread cookie crumb mixture for topping.
Use a 1/4 cup spring loaded ice cream scoop and place a level scoop full of batter into each muffin cup.
Load the lemon curd into a small sandwich size resealable bag, removing the air from the bag before sealing. Squeeze the curd to 1 corner of the bag and use scissors to snip a 1/4- inch piece from corner of bag; set aside.
With a damp finger or the end of a wooden spoon dipped in water, make a shallow indentation into the center of each cupcake. Pipe 3/4 to 1 teaspoon lemon curd into each indentation. Sprinkle tops of cupcakes evenly with remaining shortbread cookie crumbs.
Bake for 21 to 23 minutes, rotating pans halfway through baking, until edges of cupcakes are lightly golden brown.
Serve cupcakes warm from the oven or at room temperature.
A viewer, who may not be a professional cook, provided this recipe. The Food Network Kitchens chefs have not tested this recipe and therefore, we cannot make representation as to the results.