1teaspoonfinely grated lemon zest(from an organic lemon)
Sea salt and freshly ground pepper,to taste
Method
Fill bowl with ice water. In large pot of boiling salted water, blanch the green beans until crisp-tender, 3 to 5 minutes. Or to desired tenderness. With slotted spoon, transfer to a bowl of ice cold water to stop them from cooking further. Repeat with yellow beans.
Once beans are cool, drain and pat dry with a clean kitchen towel. Cut the green and yellow beans in half and transfer to a large serving bowl.
In a small bowl, mix together the dressing ingredients (lemon juice, mustard, garlic, oil, tarragon, lemon zest, salt and pepper) until well combined.
Add the white beans, tomatoes, onion and parsley to the bowl with the green and yellow beans. Pour over the dressing and toss gently to combine.
If desired, garnish with a few toasted and chopped walnuts (or serve on the side). Enjoy!
Notes
If you prefer, use all green beans or all yellow beans instead of a mix.