Make the Vinaigrette: Add the garlic, lemon juice, oil, mustard, salt, and pepper to a small bowl. Whisk well and set aside for 5 minutes while you prep the remaining ingredients; the lemon juice will mellow out the flavor of the raw garlic.
Make the Salad: Add the beans, cucumber, bell pepper, dill, and green onions to a large bowl. Add the dressing to the bowl and then mix well until evenly incorporated. Season with additional salt and pepper to taste, if necessary.
Serve: Serve immediately, or store in the fridge for 15 to 30 minutes before serving, to allow the flavors to combine. Leftovers will keep in the fridge for up to 5 days.
