For centuries, candles have been utilized for light, decoration, religious ceremonies and much more. The production of modern candles is a complex process, susceptible to several hurdles. Their main constituent, paraffin wax — which is desirable for its relatively low melting point of ~60°C  — experiences volatile changes in cost as it is a by-product of crude oil production . Additionally, during cooling, different parts of the jar candle solidify at different rates due to low heat conduction throughout the wax. This leads to uneven settling (referred to as surface undulation), which forms a cavity in the center of the candle and requires a post-process void-filling operation (see Figure 1).