Preheat your grill to medium-high heat.
Cut the avocados in half, remove the pits, and brush the cut sides with a little olive oil to prevent sticking.
Place the avocado halves, red onion slices, jalapeño halves, and lime halves on the grill grates. Grill for about 2-3 minutes per side until they are nicely charred and grill marks appear. Remove from the grill and let them cool slightly.
Once cooled, scoop out the flesh from the grilled avocados into a mixing bowl. Mash the avocado with a fork until you reach your desired consistency (smooth or chunky).
Finely chop the grilled tomatillos, red onion and jalapeño, and add them to the mashed avocado. Add the cumin.
Slice the Cherry or Grape Tomatoes in half or quarters. Chop the fresh cilantro. Add both to the mashed avocado.
Squeeze the juice of one lime into the bowl. Drizzle with olive oil and season with salt and black pepper.
Gently mix all the ingredients together until well combined.
Taste and adjust the seasoning if needed, adding more lime juice, salt, or pepper according to your preference.
Transfer the grilled guacamole to a serving bowl and garnish with additional chopped cilantro if desired.
Serve the grilled guacamole with tortilla chips or as a topping for grilled meats or tacos.