White Bean Salad with Tomatoes and Crisped Sage

Place beans in a large pot and fill with just enough water to cover. Simmer until beans are tender, 1 to 1 1/2 hours. Just before they’re done cooking, season beans with 1/2 teaspoon salt and 1/4 teaspoon pepper (if you season any sooner, skins of beans may split and centers may harden). Drain, if necessary, and transfer to a large bowl. Meanwhile, with a mortar and pestle, crush garlic and 1 teaspoon salt until a paste forms. Add mustard and mix well. Add vinegar. Gradually whisk in olive oil until a smooth emulsion forms. Pour mixture over beans while still warm. Add tomatoes and onion; toss to coat and set aside. Pour in enough canola or grapeseed oil to cover the bottom of a large skillet and place over medium-high heat until oil is very hot but not smoking. Add sage leaves in 1 layer, sprinkle with salt, and fry lightly until crisp, about 2 minutes. (If leaves are crowded, fry in batches.) With a slotted spoon, remove to a plate covered with paper towels; let drain. Sample salad and adjust seasoning to taste. Sprinkle with sage leaves just before serving.