Thaw the shrimp tails if possible. Cut the garlic and onion into cubes and sauté with oil in a pan until translucent. Then put the prawn tails in the pan and fry for about 8-10 minutes.
Add the remaining ingredients, i.e. canned tomatoes, cream, tomato paste and Italian herbs (fresh, frozen or dried - best basil, oregano, rosemary) and, if you like, chilli to the pan.
Since the prawn tails are always too few for me, I also add a small pack of peeled and cooked prawns, but it`s not a must.
Meanwhile, bring the salt water for the spaghetti to the boil. Boil the spaghetti and in the meantime simply simmer the sauce in the pan over a low heat, season with salt and pepper.