Spaghetti is a long, thin, cylindrical, solid pasta.
It is a staple food of traditional Italian cuisine. Like other pasta, spaghetti is made of milled wheat and water.
Italian spaghetti is made from durum wheat semolina, but elsewhere it may be made with other kinds of flour.
Originally spaghetti was notably long, but shorter lengths gained in popularity during the latter half of the 20th century and now spaghetti is most commonly available in 25–30 cm lengths.
A variety of pasta dishes are based on it. (source)
So can hamsters eat spaghetti noodles?
Yes they can eat spaghetti noodles. It is better that they are cooked as they are too awkward for them to eat dry. Other types of dry pasta such as fuseli is much more consumable to them.
Make sure they are cool before feeding them and only give them a little as it holds no nutritional value for them.
It shouldn’t have any additional spices, sauces or flavorings on it. Just plain spaghetti.