Implementations of the present invention relate to systems, methods, and apparatus for manufacturing aesthetically pleasing architectural resin panels having a thick three-dimensional interlayer. In particular, at least one implementation includes a layup assembly that includes a decorative interlayer, positioned between resin sheets, that decorative interlayer comprising one or more three-dimensional decorative objects and one or more resin blocks. At least one implementation also includes a single-step lamination or pressing process that uses a combination of heat and pressure to melt the resin sheets and the resin blocks together, forming a decorative resin panel which includes the three-dimensional objects.