To your Slowcooker add the chicken breasts, cooked chorizo, 2 tbsp pesto, sundried tomatoes, sliced garlic cloves, 150ml of chicken stock, and tsp basil. Cook on high for 2.5 hours.
Then add 350g dry penne pasta and 500ml of chicken stock. Cook again on high for 45 minutes, stirring after 30 minutes if possible.
Stir in 250ml of double cream and spinach, and cook for a few more minutes until the spinach wilts. Serve in bowls and top with Parmesan if desired.