The secret to perfect noodles is to use plenty of salt when boiling the noodles or pasta water, stirring the noodles or pasta initially to prevent the noodles or pasta from sticking and cooking the noodles or pasta to just before al dente, and reserving the starchy noodle or pasta water, and then finishing the cooking of the noodles or pasta directly in the sauce with some of the reserved water, which creates a flavorful and cohesive dish.
Also when making the perfect noodles or pasta, avoid adding oil to the water, as the oil in the water prevents the sauce from clinging to the noodles or pasta and unless making pasta salad, don't rinse the noodles or pasta.
The reason why pasta always tastes better in a restaurant is because of techniques like salting water heavily, using generous amounts of fat like butter/oil, finishing the pasta in the pasta sauce, reserving the starchy pasta water for emulsification and also using high quality and fresh ingredients like eggs, flour and cheese.
Restaurant chefs also build complex flavors for their pastas, through longer simmering of the pasta and layering salt and fat, which creates a richer and more cohesive dish than many people at home can achieve.
Instead of just pouring the sauce over the pasta, chefs in restaurants will toss the al dente pasta directly into the simmering sauce to allow the pasta to finish cooking in the pasta sauce and absorb flavors.
Pasta water is also key to making great restaurant quality pasta as the starch pasta water is added to the pasta sauce to emulsify, thicken and cling the sauce to the pasta noodles.
Restaurants use plenty of butter, salt and olive oil that is often seasoned like the sea, to enhance the flavor and texture of the pasta.
And sauces are often simmered longer in restaurants to develop deeper and more complex flavors for the pasta.
Experienced chefs in restaurants also have perfected these steps and can also adjust ingredient variations and ensure consistency
Many restaurants also use fresh and high quality pasta that is sometimes made in house or high quality imported dry pasta.
And restaurants also invest in better ingredients like good olive oil, flavorful cheeses and farm fresh eggs to also elevate the pasta dish.