Brush the shiitakes clean with kitchen paper or a brush. Do not to use (too) much water. Roughly slice the shiitakes and measure out the teriyaki marinade and sunflower oil. Now add these ingredients together in the pan on medium-high heat. Stir well, the shiitakes are ready after about 5 minutes. In the meantime, toast your bread.
Before topping the toast, you need to mash the avocados. This should preferably be done at the end so that the avocado stays nice and green and fresh.
Scrape the pulp from the skin and place in a bowl, mashing well with a fork. If the avocado is very ripe, this will be very easy. You can make it as coarse or smooth as you like. Add the juice of half a lime and salt and pepper to taste. Be careful when seasoning the avocado, because the shiitake with teriyaki already have a lot of flavour. It will be quite nice to have a fresh avocado mash on the side.
Now take your toast, top it with the avocado mash, and scoop the shiitake on top. Top them off with the mix of black and white sesame.