Preheat oven to 350 degrees F.
Cut or tear the bread into bite-sized cubes. Place it in a shallow baking dish and drizzle with the milk to saturate. Let it sit for 30 minutes, gently tossing things around occasionally to ensure that the bread is soaking up the milk uniformly.
Heat a large heavy-bottomed pot or Dutch oven over medium-high heat. Add the sausage and cook through, crumbling as it cooks. Stir in the onion, celery, parsley, and garlic. Add a pinch of kosher salt and a few grinds of black pepper. Cook until the onion and celery begin to soften, stirring occasionally.
Add the kale, ½ cup of water and another pinch of kosher salt. Cook until the kale wilts. This should take about 5 minutes.
Transfer the bread to a large bowl. Add the sausage and kale mixture to the bowl along with the parmesan cheese, basil, rosemary, sage, 2 pinches of salt and several turns of black pepper. Gently toss the mixture until all ingredients are evenly incorporated. Give the dressing a taste and season with more salt and pepper, if needed. Transfer the dressing to a 9x13-inch baking dish.
Whenever you're ready to bake and eat the dressing, you'll want to preheat the oven to 350 degrees F and bake uncovered until hot (at least 150 degrees in the center) and lightly browned. This should take about half an hour.