Wipe mushrooms with a damp paper towel, remove stems + scoop out gills; thinly slice, heat 1 tbsp oil in a skillet over med-high + sauté 3-4 min until tender; add salt/pep

In batches, heat 4 tortillas in skillet over med-high, 30 sec or until warm; add mushrooms to tortillas

Add 1-2 tbsp of drained pickled red onions to each taco

Dollop on 2 tbsp guacamole to each

Wash + dry cilantro, roughly chop leaves; add to tacos