How to Make It
Make the chicken In a large bowl, stir together all of the ingredients except the chicken. Add the chicken thighs and toss to coat. Let stand at room temperature for 20 minutes.
Meanwhile, make the corn In a small bowl, mix the butter with the miso and scallion.
Light a grill and brush the grate with canola oil. Grill the corn and chicken over moderate heat, turning, until charred in spots and the chicken is cooked through, about 10 minutes for the corn and 12 to 15 minutes for the chicken. Transfer the corn to a large platter and slather with the seasoned butter. Arrange the chicken alongside, garnish with sliced scallion and serve warm.