In a large deep dish, fry pan or pot on a medium heat, bring the olive oil to heat. Add the onion, chili and garlic to the pan and sauté for 5 minutes, stirring often. Add the chorizo to the pan and cook for 5 minutes or until the chorizo is cooked through and slightly caramelised.
Add the white wine to the pan and bring to the boil. Reduce the heat and simmer for 2 minutes or until half has been absorbed. Add the clam to the pot and cover with a lid. Cook for 5 – 7 minutes or until the clams shells have opened, shaking the pot occasionally.
Remove the lid and stir the butter through the sauce until emulsified and you have a smooth and silky sauce. Sprinkle over a large handful or parsley and stir through. Serve immediately with slices of olive oil fried sourdough.