How to Make It
Heat 2 tablespoons of the oil in a large saucepan over medium heat. Add the onion, celery, ½ teaspoon salt, and ¼ teaspoon pepper. Cook, covered, stirring occasionally, until tender, 10 to 12 minutes; stir in the tomato paste and cook, stirring, for 1 minute.
Add the tomatoes (and their liquid) and break up with a spoon. Add the beans, thyme, and ½ cup water and bring to a boil. Reduce heat and simmer, stirring occasionally, until thickened, 6 to 8 minutes.
Meanwhile, heat the remaining 2 teaspoons of oil in a large skillet over medium-high heat. Add the sausage and cook, turning occasionally, until browned and cooked through, 10 to 12 minutes. Serve the sausage with the beans and sprinkle with the parsley.