How to make best chicken fricasee for weekend dinner

Ingredients

• Chicken legs ((500 gms))
• 2 tablespoons butter
• 1 tablespoon extra-virgin olive oil
• Pepper ((1 tbsp))
• 1 onion (,chopped(1 cup))
• Mushroom 2 cups diced
• 1 celery stalk (, small pieces)
• Garlic ((2 cloves))
• 2 tbsp of white wine
• 2 tbsp of refined flour
• 2 cup chicken stock
• 2 to 3 bay leaves
• 1 cup of fresh cream
• a bunch of thyme leaves
• 2 yolks
• 1 tbsp of lemon juice