Well, XML Sitemap Feed works on WP in normal mode too so you do not need to use multi-site... I don't know if it's at all possible for you to revert to a backup from before the conversion but I have the impression the complications of multi-site is not what you need on your site. Unless you are planning to start different sites on the same installation, you are better off keeping it simple.
So my first advice would be: go back to normal / single site mode by restoring a backup.
About the FeedBurner redirect, I supppose it is your theme doing that. Look in the theme options for a setting with http://feeds2.feedburner.com/NoRecipes ...
If you decide to keep working in multi-site mode, I have some questions and suggestions for you.
One thing that is puzzeling me about your setup is this:
You have on your main site http://norecipes.com/ there is a menu item "Ingredients" that points to http://ingredient.norecipes.com/. I would have guessed that is one of your sub-sites but when I open the first article on that front page, I see the URL swap to http://www.norecipes.com/ingredient/black-cardamom
Looking at the sitemap of that sub-site on http://ingredient.norecipes.com/sitemap.xml I see more links like that. And these URLs will be regarded as EXTERNAL links which makes the sitemap invalid (no matter which pluginyou use). Trying http://ingredient.norecipes.com/robots.txt I get a 500 internal server error...
Another example, I can visit your main site front page via http://norecipes.com/ and http://www.norecipes.com/ where in that last case the www is left in front of the domain name and I do not get redirected to http://norecipes.com/... But all the links to posts do start with http://norecipes.com/ and if I try http://www.norecipes.com/sitemap.xml I get redirected to http://norecipes.com/ (without sitemap.xml)
Weird stuff going on there which needs to be taken care of first. Can you explain it to me?
Anyway, are you on your own server or a shared hosting account? I think you need to take a look at your domain pointing manager and sort out what goes where. The best thing to do on a multi-site setup is point everything to the same WP installation and avoid using any www in your domains. There is no need for www anyway and it will cause duplicate content and invalid sitemaps.
Then, if you can, set up a subdomain wildcard (*) pointer that goes to the same WP installation and let WP handle the rest. If your provider does not allow wildcards in the domain manager, you will need to configure each subdomain individually. Not a problem, as long as it is done right.