How to Make It
In a medium saucepan, cover the cannellini beans with 2 inches of water. Add the bay leaf, thyme and onion and bring to a simmer. Simmer over moderately low heat, stirring occasionally and adding more water to cover as necessary, until the beans are tender, about 2 hours. Drain and let cool completely. Discard the bay leaf, thyme and onion.
Meanwhile, in a medium saucepan of boiling salted water, cook the green beans until they are crisp-tender, about 3 minutes. Drain well and spread out on a baking sheet to cool. Pat the beans dry with paper towels. Cut the beans on the diagonal into 1-inch lengths.
In a large bowl, combine the olive oil, lemon juice, cilantro and olives and season with salt and pepper. Fold in the cannellini beans and green beans and season with salt and pepper. Serve the salad with the lime wedges.