Salad "Finger-Licking Good"

INGREDIENTS
herring fillet - 2 pcs.
chopped walnuts - 1/2 cup
champignon mushrooms - 300 g
boiled eggs - 3 pcs. 
onion - 2 heads
carrot - 1 pc.
vegetable oil - 1 tbsp
dill - 1 bunch
green onions - 1 bunch
mayonnaise - 200 g

METHOD OF PREPARATION:
1. Cut the herring fillet into small cubes and mix with the walnuts.
2. Slice the onion into half rings, grate the carrot on a coarse grater. Combine the vegetables and sauté in oil without changing the color.
3. Boil the mushrooms in salted water, cool, and slice.
4. Finely chop the eggs, dill, and green onions. Mix the onions with the dill.
5. Layer the prepared ingredients in a salad bowl in the following order, spreading mayonnaise on each layer: herring with walnuts, eggs, vegetables, mushrooms, and greens.
6. Before serving, spread the remaining mayonnaise on the salad and sprinkle with chopped greens.