Concurrent control of size, shape, and composition of nanoparticles is key to tuning their functionality with widespread applications in sensing, catalysis, cancer cell ablation, water-splitting, spectroscopy, dye-sensitized solar cells, and more. UCB inventors demonstrate unprecedented precision over the structure and composition of complex nanoparticles by fusing colloidal chemistry with plasmon assisted synthesis. They show that combining properties of light used for plasmon excitation (wavelength, intensity, and pulse-duration) with the physical properties of nanoparticles (size, shape, and composition) leads to hitherto unrealized core-vest composite nanostructures. Tunable variations in localized temperature distributions >50 degrees C are achieved over nanoparticles as small as 50-100 nm. These temperature variations result in core-vest formations with selective shell coverage that mirrors the local inhomogeneities of the heat distribution. This new class of core-vest nanoparticles (CVNs) allows plasmonic enhancement of nanocomposite functionalities that are inaccessible in typical core-shell geometries.