If using dry beans: soak beans overnight and the next day rinse the beans and boil in plenty of water with a whole onion and a bay leaf for about 30 minutes until soft but not mushy. After boiling rinse in cold water and set aside.
Prepare the dressing: In a small bowl mix with a fork the balsamic vinegar, honey, mustard and olive oil. Add pepper and salt to taste.
In a large bowl toss the spinach, mint and sundried tomato, add the beans and mix and sprinkle on top the feta. Add the dressing right before serving.
Serve with whole grain bread, breadsticks or rusks.