[header] How to make edible sand [title] Blend the chocolate and whole graham crackers in a food processor. [step] Blend on high speed for about a minute or two, until the graham crackers resemble the consistency of sand. [substeps] You can also crumble the crackers by placing them in a ziploc bag and whacking it with a rolling pin. 
This process takes a little more effort but it works just as well. [title] Pour the crumbled graham crackers into a large bowl.