One Pot Chicken Pesto Pasta Bake

• 1 tbsp extra virgin olive oil
• 1 brown onion, finely chopped
• 2 chicken breast fillets, cut into bite sized pieces
• 2 garlic cloves, crushed
• 1.75 cup chicken stock
• 300 g dried spiral pasta
• 190 g green pesto
• 200 g smooth ricotta
• 1 small head broccoli, cut into small florets
• 100 g baby spinach
• 1.5 cup grated cheese
• 0.25 cup fresh parsley leaves, roughly chopped