1. Slice 400g of brown champignons, 400g of white champignons, and 150g of Shimeji mushrooms.
2. In a pan, sauté the sliced mushrooms with salt until they are cooked through and slightly caramelized. Set aside.
3. Dice 700g of chicken breast into small pieces and mix it with soy sauce and oyster sauce then cook them in a separate pan until they are fully cooked.
4. Once the chicken is cooked, mix it with the mushrooms.
5. Place a tortilla on a flat surface and sprinkle some shredded cheddar cheese on one half of the tortilla.
6. Spoon the chicken and mushroom mixture on top of the cheese.
7. Fold the tortilla in half to cover the filling.
8. Heat a non-stick pan over medium heat and place the quesadilla in the pan.
9. Cook for a few minutes on each side until the tortilla is crispy and the cheese is melted.
10. Repeat the process with the remaining tortillas and filling.
11. Cut the quesadillas into wedges and serve hot with mayo ketchup sauce.