I made a really easy vegetable stew in the slow cooker yesterday that was pretty good.

2 carrots, chopped
1 celery stalk, chopped
half a medium/large onion, chopped
2-3 cloves garlic, minced
1 14-oz can diced tomatoes
1 14-oz can red kidney beans, rinsed and drained
2 cups tomato juice
2 cups vegetable stock
2/3 cup (dry) uncooked quinoa
1 tbsp basil
1 tbsp oregano
salt and pepper to taste
a little Tabasco sauce to taste

Combine everything in a 3 or 4 qt slow cooker and cook on low for 10 hours.

The quinoa will give is more of a stewy consistency. Leaving the quinoa out will result in a soup.