Fabrication of tunable fine texture on solid metal surfaces, often demands sophisticated reaction/processing systems. Exploiting in situ polymerization and self‐assembly of inorganic adducts derived from liquid metals (so‐called HetMet reaction) with concomitant solidification, solid metal films with tunable texture are readily fabricated. Serving as natural dimensional confinement, interparticle pores and capillary adhered thin liquid films in a pre‐packed bed of undercooled liquid metal particles lead to expeditious surface accumulation of organometallic synthons, that readily oligomerize and self‐assemble into concentration‐dictated morphologies/patterns. Tuning particle size, particle packing (flat or textured), and reactant concentration generates diverse autonomously organized organometallic structures on a metal particle bed. Concomitant solidification and sintering of the underlying undercooled particle bed led to a multiscale patterned solid metal surface. We illustrate the effectiveness of this dimensionally restricted polymerization, coupled solidification and sintering process by creating tunable features on pre‐organized metal particle beds with concomitant tunable wettability as illustrated through the so‐called petal‐ and lotus‐ effects.