Easy one-pot roast chicken

Ingredients

• 1 1/2 kg chicken
• 1 lemon (halved)
• 3 tbsp butter (softened)
• 2 tsp sumac (or mixed dried herbs or paprika...anything goes!)
• sea salt
• black pepper
• 750 g potatoes (peeled and quartered)
• 5 carrots (topped, tailed and cut into chunks)
• 2 tbsp Oil
• 100g frozen peas
• 300 ml chicken stock
• 1 tsp marmite
• oil
• 70 g plain flour
• 2 eggs
• 100 ml milk