Put the apricots in a bowl, add just enough water to cover, and let stand overnight. Drain.
In a saucepan over medium heat, combine the sugar and water. Bring to a boil, stirring to dissolve the sugar. Simmer until thickened.
Add the apricots and cook until tender, about 20 minutes. Stir in the lemon juice and continue to simmer for a minute.
With a slotted spoon, very, very carefully transfer the apricots to a baking sheet or a large plate. Reserve the syrup in the pan. Let cool to thicken slightly. If the syrup is not thick enough, reduce it further over medium heat.
If using whole apricots, carefully cut each apricot along the seam with a small sharp knife to create a pocket. Put in the peanut brittle and fill with a bit of the hung curds/yoghurt. (You have to keep a light hand, otherwise the apricot could tear.)
If using apricot halves, spoon the filling onto the centres of half of them. Top with the rest.
Place the apricots on a serving platter. Spoon the sugar syrup over the stuffed apricots, top with the almonds or pistachios. Refrigerate until the syrup is set, about 30 minutes.