Rinse the dried cannellini beans under cold water and place in a pot with enough water to cover them by about two inches. Boil, then simmer for about 1.5 to 2 hours until tender.

In a mixing bowl, whisk together lemon juice, olive oil, and Dijon mustard. Add minced garlic and chopped shallot, whisking until well combined.

In a large bowl, combine cooled beans, dressing, fresh herbs, and chile flakes. Add crumbled feta and mix gently.

Cover and let the salad marinate in the refrigerator for at least 15 minutes to develop flavors.

After marinating, gently toss the salad and serve chilled, garnished with additional fresh herbs if desired.