This is not a sweet dressing, but very flavourful and delicious. Just a word of warning: because of it's vibrant purple hue, you may not want to wear white when making or eating it!
2 cups fresh or frozen blueberries
Half a red onion, chopped (about 3/4 cup)
2 cloves garlic, minced
1/2 cup water
2 tbls balsamic vinegar
1 tbls dijon mustard
1/4 cup red wine vinegar
1/2 tsp salt, or to taste
Fresh ground black pepper, to taste
Place berries, garlic, onion, water and balsamic in a sauce pan. Bring to a boil over medium heat. Turn heat down and simmer for about 10 minutes. Let cool. Place in blender along with mustard and puree until desired consistency is reached. Add vinegar and seasonings. Will keep in the fridge for up to 2 weeks.