If it is in true use-- I give you the Italian pronunciation:
Ah-Zee-Ah
"A" is said as the "A" in "Father." An "S" found between two vowels creates "Z." Stress the "I" to "EE." And end with "A" as in "Father," once again. A note: The final three letters ("-sia") will be sandwiched a bit more when spoken... Perhaps taking the "I" sound to a short "EE," nearly "Zyah."