I'm curious as to what kind of onion is usually used in Italian cooking. When making the tomato sauce or the ragu I have used yellow onions, while others have used white onions.

Just wondering which way you lean.

White, yellow and red are often used. It depends on how much of a sweet or potent flavor you want. Here is a good link which talks all about onions. Really, whichever you have on hand will be fine, although consider the color when using red. Hope this helps!

how much meat,one lb etc

All of the quantities are listed in step 2 of the text recipe. Hope this helps.

i have been reading a lot of different recipes for bolognese. what is the difference between adding tomato paste and canned/strained tomatoes? what is the difference betweeen adding white or red wine? thanks

First of all, tomato paste is generally much thicker so will make the sauce thicker. You can also thicken a tomato sauce if using runnier tomato product (e.g. canned/strained) by simply simmering it and evaporating (reducing) some of the liquid.

Most importantly though, you should be thinking about ensuring that you have good canned tomato products. I searched "tomato" on Rouxbe here to find answers to these kinds of questions:

http://firewater.rouxbe.com/search?q=tomato&x=0&y=0
(click on the 'tip and technique' tab)

Re: white and red wine, I turn the question back to you. What do you think? Part of teaching is to help our students trust their own instincts.

Joe

i imagine the red wine will give the sauce a much more dark, overall tone. the white wine will make it lighter.

Indeed you are correct Sushruth. To add to that, not only will the color be a bit different the flavors of course will also be affected by the different flavors and strengths of the wine. Cheers!

I have used a larger pot, so the liquid evaporated sooner. Is it okay to add more liquid or would that change the overall flavor?

I've also substituted the pork with fresh sausage. It tastes good, but the texture is different. It seems a bit pasty. I'm guessing it is because of the fat in the sausage.

cheers.

By mixing the ragu and tomato sauce, is it enough for a good spaghetti sauce?? Is there other ingredients we might add?
Thanks

I'm sure this combination alone would be delicious. Give it a try and let us know how it turns out for you. Cheers!

Is there a reason why salt is not added throughout the cooking process ( sweating the mirepoix and when adding the meat), and to only season the sauce at the very end?

The reason the salt is not added throughout for this particular recipe is merely because this recipe is by Mario Batali, so we kept it as he did it. Cheers!