Chunky Italian Vegetable Stew

Name: Chunky Italian Vegetable Stew
Ingredients: 6 tablespoons olive oil; 2 leeks (white and light green parts only), sliced; 4 cloves garlic, chopped; 2 bunches Tuscan or Lacinato kale or 1 medium bunch curly kale (about 20 ounces total), thick stems discarded and leaves sliced; 4 cups low-sodium vegetable broth; 2 15-ounce cans butter, cannellini, or corona beans, rinsed; 1 28-ounce can diced tomatoes; kosher salt and black pepper; 1 ounce Parmesan, grated (about ¼ cup), plus more for serving; 6 thick slices country bread, toasted