These are the restaurants whose margheritas (or margaritas) I have sampled most recently:
Bambalino’s – Good / Satisfactory
Barry’s Pizza – Fair / Poor
Bistro Menil – Good
Fratelli’s – Good
Fresco Italian Café – Good / Very Good
Grimaldi’s (CityCentre) – Good
Pronto (Montrose) – Satisfactory / Fair
The La Spezia the other Saturday at Bistro Menil. It's their version of the margherita, and pretty good, too.