Vegan 'Tuna' Sandwich

Thinly slice red onion and place it in a jar.

Add salt, a bay leaf, and black peppercorns to the jar.

Pour boiling water, apple cider vinegar, and maple syrup over the onions. Close the jar and let it pickle.

In a bowl, mash chickpeas with a fork until they have a flaky consistency.

Add finely chopped pickle, celery, onion, and nori to the mashed chickpeas.

Add mustard, vegan mayo, and salt, then mix everything together well.

Toast two slices of bread until golden brown.

Layer arugula on both slices of bread, then add the vegan 'tuna' mixture to one slice.

Top the 'tuna' mixture with sliced avocado, tomato, and the pickled red onions.

Place the second slice of bread on top, slice the sandwich in half, and enjoy.