A spasticification of the word 'schnizzle'. Invented to parody the ridiculousness of most rappers (esp. American ones) and the popularisation of their stupid jargon.
"Snoop dogg? Wow, I DO totally LOVE his work. Such musicianship. Schpazzle."
To shjazzle is to make female and male private parts look terrible in their appearance, often accidently.
Also, to really make something look bad when trying to make it look good.
Dame Edna often shjazzles her va-jay-jay with Swarovski crystals.
A Schnozzle is when you sneeze and a large amount of snot (also known as bogies or nasal mucus) is produced from this sneeze, either into a tissue or into your own hands. This is not regarded as classy in the upper class world.