Heat the oven in the Broil mode to 550° F.
Lightly coat the avocado, corn, scallions and red onion quarters in heat tolerant oil, place on the blue oven tray lined with foil, shiny side down and cook on rack position 4, counting up from the bottom with the door closed, until charred and tender. Approximately 8 minutes.
Remove the tray from the oven, finely dice the charred scallions and mix with a little lime juice and salt. Mash half of the avocado together with the scallion paste, oat milk, cumin, lime juice and zest and season with salt and pepper. Cut the remaining half avocado into chunks and fold in gently. Remove the corn kernels from the cob.
Cooking Option - if you have a Gaggenau grill, the avocado, onion, corn and scallions can be charred on the grill, using level 8.