Light-emitting diode (LED) packages with improved heat transfer paths for LED dies encased therein when compared to conventional LED packages are provided. For some embodiments, the LED package includes a ceramic substrate having a top cavity with one or more LED dies disposed within and having a bottom cavity for receiving a metallic insert to dissipate heat away from the LED dies. For other embodiments, an LED package is provided that includes a ceramic substrate having a heat spreader coupled to thermal vias filled with a highly thermally conductive composite.