Chicken and mushroom pie: Now that's comfort food

Ingredients

• 3 boneless and skinless chicken breasts, cubed
• 150 g button mushrooms, quartered
• 1 small onion, chopped
• 1 clove garlic, finely chopped
• 50 g butter
• 2 tbsp plain flour, plus more for dusting
• 300 ml milk
• 200 ml chicken stock
• 200 g peeled baby carrots
• 100 g leek stems cut into quarters
• 100 g green beans
• 20 g micro greens
• white pepper to season, freshly ground
• 2 tbsp chives, chopped
• 2 tbsp parsley, chopped
• 60 g grated cheese
• 1 egg, beaten
• 2 tbsp olive oil
• salt to season