Wash the corn and then cut the kernels from the cobbs. Set aside. Wash and cut the peaches into chunks. Heat a griddle pan over medium heat and add the olive oil to the pan. Add the corn and peaches and grill until they turn golden brown, tossing occasionally. (See below for outdoor gill method.)
While the corn and peaches are grilling, make the miso dressing. Blend all the dressing ingredients together in a blender until smooth. Set aside.
If your sunflower seeds are raw, toast them in a small, dry skillet over medium heat, tossing frequently until they are golden brown. Place them into a bowl and set aside.
Cut the avocado into chunks.
Place the grilled corn and peaches into a medium-large bowl along with the avocado and ⅓ cup of the miso dressing. Toss to combine. Finally add the toasted sunflower seeds, and squeeze lime juice over the salad. Give the salad one more toss and serve! This salad can be made ahead. Add toasted sunflower seeds just before serving. Save the reserved dressing and add more, if needed, before serving. Keep this salad stored covered in the refrigerator for up to 2 days.
Outside Grill Method
Grill the corn and peaches on an outdoor grill. Omit olive oil and grill the corn whole and peaches in half. After grilling, cut the corn from the cobbs and slice the peaches into smaller pieces. Then follow the remaining instructions.