Since I have the tools, a lefthand drill bit and an angle drill would be my approach. That'll fix it in short order.
Just make sure you center-punch the broken bold first so that you drill as closely down the exact center of it as possible, and the rest is very easy. Step up in drill bit sizes until it comes right out.
And however you work on it, improvise a fender cover with some blanket taped to the fender's hood seam, or the like. If you don't, you're garaunteed to drop a tool and scratch the fender.
2014 Sterling Gray GT Premium with silver stripes / MT-82 / Brembo / Recaro
Steeda Sports | Koni Yellows | BMR Panhard and LCA Brackets
MGW shifter | Borla S-types