Creamy mushroom & Swiss chard tagliatelle

Ingredients

• 500 g tagliatelle 
• Olive oil
• 8 seasoned pork sausages, casings removed 
• 1 red onion, roughly chopped
• 3 garlic cloves, chopped
• 250 g Portabellini mushrooms, roughly torn
• 125 ml white wine
• 125 ml cream
• 100 g chard, stems removed, leaves chopped
• Salt
• Pepper 
• Dried chilli flakes, to taste
• Parmesan shavings, to serve (optional)