To brew this sour blonde with apricot, mash at high temp for a short amount of time: 160°F (71°C) for 15 minutes. The idea is to create a wort with low fermentability and even some starch remaining.
Ferment with primary strain at 68°F (20°C) for ale
After primary fermentation is complete, rack to your aging vessel of choice (shoot for as low oxygen permeability as possible to limit acetic acid) and add Brett/bacteria blend.
Once souring has reached our satisfaction (8-12 months typically), add the apricots. Select a variety with intense flavor (Blenheim, Golden Sweet, etc.). You can choose to throw a few pits in for character.
After 2-3 months, rack off apricot sludge and package.