Preheat the grill and the grill fry pan.
Combine the olive oil, salt, chile flakes and garlic in a large bowl and mix until the salt is dissolved. Toss in the chard to coat.
Pour the chard into the grill fry pan and close the grill lid. Cook until the greens are wilted, stirring and tossing occasionally.
Transfer to a clean bowl and toss with the apple cider vinegar and bacon. Season with salt and black pepper.