A method of customizing the sole structure of an article of footwear includes providing a sole structure with a sole component having an inner surface and an opposite-facing outer surface. The sole component includes a plurality of inner recesses extending from the inner surface and a plurality of outer recesses extending from the outer surface, the plurality of inner recesses include a blind-hole inner recess, the plurality of outer recesses include a blind-hole outer recess, and the blind-hole inner recess is generally aligned with the blind hole outer recess along a vertical direction. The method further includes adjusting the flexibility of the sole component by selectively cutting or removing material from one or both of the blind-hole inner recess and the blind-hole outer recess.