Preheat the oven to 350°F (175C/155C Fan) and prepare a 12 hole cupcake tin with cases.
Juice half a lime into a ½ cup measure and top up with whole milk. Give this a stir and set aside for 10 minutes.
Meanwhile, sift the flour, baking soda, baking powder and salt together and set aside.
In a large bowl, beat together the butter and sugar until light and creamy. Add the eggs one at a time, beating after each addition, and add the tablespoon of Pisco.
Add half of the flour mixture and beat until just combined. Then add the soured lime milk, beating to combine and then the rest of the flour along with the lime zest. Beat until just fully incorporated.
Place in the centre of the oven and bake for 25-30 minutes, until a toothpick inserted in the centre of one of the central cupcakes comes out clean. Remove from the oven and cool on a wire rack.
Once cool, use a large piping tip or a sharp knife to core out the centre of the cupcake for filling. Take care not to cut to the bottom as you will want cupcake at the base. Reserve the centre cake pieces.
Fill each cupcake with a dollop of lime curd (about a teaspoon). Replace the cake cores on top of the curd to act as a cork.