Lightly toast the bread.
Slather one slice with tve vegan garlic aioli. Set aside.
Add the cheese to the other slice of bread. Warm up a small skillet. Add 1 teaspoon oil. When the oil is hot, add the bread, cheese side up. Then turn heat to low. Add one small ice cube and quickly cover the sandwich with a lid. The steam from the ice will melt the cheese. Lift lid, turn off heat. Transfer the bread with the melted cheese to a cutting board or assembly area.
Turn the heat back on to medium. Add another teaspoon oil. When the oil is hot, add in the red onion slices. Cover with lid and allow them to cook for a minute. Remove lid and keep cooking on medium-high until they soften and lightly blacken. When they are done, turn off the heat and transfer the onions to the bread with the cheese. Lay the onions right on top of the melted cheese.
Next, add the avocado to the bread with the aioli. Smash the avocado into the bread using a fork.
Add the tomato, pickle and leafy greens.
Close up the sandwich. Slice and serve.