Preparation

• Spread the beans on a baking sheet. Rinse the beans well, put them in a large pot, cover by 3 to 4 inches of water, add the salt, onion, and rosemary, and bring to a boil. Reduce the heat to a simmer, cover and cook until the beans are very tender but not falling apart, 45 minutes to 1-1/2 hours, longer if necessary. Start checking early because beans cook at different rates; if the water level gets low, add more. When the beans are cooked, let them cool in their liquid for about 15 min. and then drain. Transfer them to a large bowl and keep them warm. (If using canned beans, rinse and drain them well.)
• Meanwhile, in a small saucepan or skillet, combine the olive oil, garlic, and rosemary. Heat gently until the rosemary starts to sizzle lightly, remove the pan from the heat, and leave to steep for about 20 min. Discard the rosemary.
• Take the garlic cloves from the oil (reserve the oil) and put them in a food processor, along with the anchovies, grated cheese, salt, pepper, zest, and lemon juice. Process to a fairly smooth mixture. Taste for seasoning; the dressing should be highly seasoned.
• Toss the dressing with the warm beans, using a rubber spatula to gently fold so the beans get well coated but not smashed. Let the beans sit for a few minutes and then toss a few more times. It may seem like too much liquid at first, but the beans will gradually absorb it all. Fold in the reserved infused oil, the tomatoes, and the parsley. Taste for seasoning and serve.