Start by washing the trout, remove the head, fins, tail, and skin.
With great care, he begins to take away the thorns he has; this is done by gently running his hands through the trout’s body, and when he feels the thorns, then remove them.
When you have done this, add the lemon juice to the trout and let stand for about 20 to 30 minutes.
Cut the avocados in half, remove the seed and the peel, and with a fork, mash until you get a puree.
Add mayonnaise, cream, a little salt, and stir.
Cut the onion into thin feathers and reserve.
Now, bring the roasted trout, add a little salt and cook over medium heat on both sides until well cooked.
To assemble the dish, place mashed avocado in the bottom, followed by the onion in plums, the trout, the cornstarch, and finally, the coriander.
You can serve accompanied by crispy slices of green banana.