Rinse the dried cannellini beans under cold water, then cover them with water in a large pot, ensuring at least two inches above the beans. Bring to a boil, reduce heat, and simmer for about 1-1.5 hours until tender. Drain and set aside.

In a medium bowl, whisk together fresh lemon juice, Dijon mustard, minced garlic, and chopped shallots. Gradually add olive oil while whisking until emulsified. Adjust seasoning.

In a large mixing bowl, combine the cooked white beans with the dressing, add a pinch of chile flakes and crumbled feta. Toss until well combined.

Transfer to a serving dish, garnish with parsley and chive blossoms. Serve immediately or chill for an hour before serving.