A bastardised version of "Fo' sho' nigga", which is a bastardised version of "for sure my nigga", which is a bastardized version of "I completely concur my african-american brother"
Is that your hoe? Nigga she fly.
F'shizzle my n'izzle
Fo' shizzle ma' nizzle" is a bastardization of "fo' sheezy mah neezy" which is a bastardization of "for sure mah nigga" which is a bastardization of "I concur with you whole-heartedly my African American brother"