Chicken, Mushroom and Leek Lasagne - Pinch Of Nom

Ingredients

• 6 dried lasagne sheets
• 500 g diced chicken thighs
• 1 medium onion, (peeled and finely chopped)
• 1 medium leek, (trimmed and finely chopped)
• 2 garlic cloves, (peeled and crushed)
• 200 g white mushrooms, (thinly sliced)
• ½ tsp mustard powder
• 2 tbsp Dijon mustard
• 1 chicken stock cube
• 275 ml boiling water
• 2 tsp fresh thyme leaves, stalks removed and chopped
• 100 g reduced-fat cream cheese
• salt and black pepper, to taste
• low-calorie cooking spray
• 500 ml skimmed milk
• 25 g reduced-fat spread
• 3 tbsp cornflour
• 3 tbsp cold water
• ¼ tsp mustard powder
• 100 g reduced-fat mature Cheddar cheese, (finely grated)
• salt and black pepper, (to taste)
• 20 g reduced-fat mature Cheddar cheese, (finely grated)