How can I fix a bitter raw leek soup? My son just got his braces adjusted and in a panic to make him a lunch for school, I made the following soup in my vitamix with what I had on hand. The problem is that the soup is very bitter (raw leek I suspect). I usually sauté the leeks first but didn't have time this morning. If I cook it on the stove, will the bitter taste go away? What if I blended in a head of raw broccoli? 

Here are my ingredients:
1 raw leek...stalk and all, 
1 small avocado,
2 stalks of celery,
About 8 cherry tomatoes,
½ cup of potato and garlic mash from a previous dinner,
about 1 cup of ready made chicken broth.

The consistency is awesome. I just need to fix the bitter taste and nastiness of eating raw onions! Thanks for your suggestions.
Raw leeks are quite strong and will mellow if cooked, so get it up to temperature for awhile and see where you get. I suspect that will get you much of the way there. If not, some mild acidity will help, adding a squeeze of lemon juice may do it for you.