Start this recipe by placing the clams into a bowl of cold water for 2 hours in the fridge so they spit out any sand. When ready, heat a large pan of salted boiling water and cook the gluten-free pasta. Meanwhile, heat the oil in a pan and quickly brown the chorizo for 3-4 minutes. Add in the butter, onion and garlic and saute for 3-4 minutes to soften. Next, add in the clams, splash in the wine to evaporate and season with salt and pepper. Add in the stock, give the pan a shake and put the lid on. Steam for 4-5 minutes until the mussels are cooked through and opened up. Add in the lemon juice and zest, parsley and cooked spaghetti and toss around to coat. Serve immediately into 2 bowls with lemon wedges on the side.