For Piri Piri Chicken:4 to 8 fresh hot chilis, depending on how hot you want it5 garlic cloves2½ teaspoons kosher salt¼ cup red wine vinegar⅔ cup olive oil, plus 1 tablespoon for grilling1½ pounds boneless, skinless chicken thighs, cut into 1½-inch chunksBamboo skewers, soaked in water for at least 1 hour, or metal skewersFor Cabbage and Cucumber Slaw¼ small head green cabbage, very thinly sliced (about 2½ cups)¼ cucumber, halved lengthwise and thinly sliced on an angle (about ¾ cup)¼ white onion, very thinly sliced (about ¼ cup)¼ cup loosely packed fresh mint leaves, thinly sliced2 tablespoons olive oil2 tablespoons fresh lime juice1 tablespoon finely grated lime zestKosher salt, to tasteGrilled flatbreads