A method is disclosed for producing structures having a plurality of stems extending away from a fenestrated base to undercut ends. Such structures include slidingly-engaging fastener portions, hook-and-loop hook portions, self-engaging fastener portions, and other structures with similar aspects. The method includes providing a set of partially bypassing dies to define a fenestrated common cavity contiguous with pluralities of undercut stem chambers, filling the cavity with a moldable material, and ejecting the resultant product. The resultant product includes a plurality of undercut stems spaced away from a base with undersides projecting over fenestrations in the base.