Heat the oven to 425°F. Set a rack in the middle of the oven so the casserole browns evenly.

Put a 10-inch oven-safe skillet or a 3-quart Dutch oven on the stove over medium-high heat. Add 1 tablespoon of the olive oil and let it heat for about 30 seconds.

Add the sliced chicken sausage to the skillet in a single layer. Cook for 4 to 5 minutes, stirring once or twice, until the sausage is browned on the edges.

Transfer the browned sausage to a plate. Leave any oil in the skillet so it can flavor the vegetables.

Add the chopped onion, sliced carrots, and sliced celery to the skillet. Cook over medium heat for 6 to 7 minutes, stirring now and then, until the onion looks soft and the carrots have started to lose their raw crunch.

Add the chopped garlic and chopped rosemary to the skillet. Cook for 1 minute, stirring, until they smell fragrant.

Add the tomato paste to the skillet. Stir it into the vegetables for 1 minute, until it darkens slightly and coats the vegetables.

Add the drained cannellini beans and the chicken broth to the skillet. Stir well and scrape the bottom of the pan with a wooden spoon so nothing sticks.

Return the browned sausage and any juices from the plate to the skillet. Bring the mixture to a gentle simmer and cook for 5 minutes, until the broth looks slightly thicker.

Add the chopped kale to the skillet a handful at a time. Stir after each addition and cook for 2 to 3 minutes, until the kale is wilted and mixed into the beans. Taste the broth and season with salt and black pepper.

Make the topping: Put the panko breadcrumbs, 1/4 cup of the grated Parmesan, and the remaining 1 tablespoon olive oil in a small bowl. Stir until the crumbs are lightly coated.

If your skillet is not oven-safe, transfer the bean mixture to a 2-quart baking dish. Spread the breadcrumb mixture evenly over the top, then sprinkle on the remaining 1/4 cup Parmesan.