Soot

Soot would be left after any flammable block burns away, it would accumulate in layers like snow, and if the block underneath it is destroyed it will fall, soot layers would be stackable, and after walking over a soot layer you would leave black footprints as a particle for 3-4 blocks. Soot cannot be crafted into anything, but when dug with a shovel with give you the soot item, you can click any solid block with soot and it will use the item, and leave a temporary black marking on the block, the timing of how long the marking lasts can be altered with commands, but it has a default of 5 minutes, this ends early when the block is exposed to rain. If you collect the soot layer with a silk touch item, it will drop the soot layer, which can either be crafted into soot or placed back down somewhere else.