The improved mold assembly for cultured marble molding is provided. The mold assembly can comprise a male mold portion and a female mold portion. The assembly can further comprise a molding tool. The molding tool can have a side wall having an upper curved s and a lower curved portion. The molding tool can be constructed from a flexible and/or soft material. The lower curved portion of the molding tool can be coated with a gel coat having a first color. The molding tool can facilitate molding of a countertop having a recessed bowl portion having a color different from a counter portion of the countertop.