Bring a large pot of salted water to a boil to prep the pasta. Slice the brussels sprouts into shreds and then do the same with the kale leaves.
Heat a large skillet over medium-low heat. Add the butter and olive oil. Once melted, add the shallot with a pinch of salt and pepper. Cook, stirring occasionally, until the shallot softens, about 5 minutes. Stir in the shredded brussels sprouts and kale. Add another pinch of salt and pepper. At this point, your water is probably boiling and you can cook the pasta according to the directions.
Cook, stirring often, until the brussels and kale soften, about 6 to 8 minutes. Stir in the garlic and cook for 5 minutes more.
To toast the pine nuts, place them in a dry skillet and heat over medium- low heat. Stir frequently with a wooden spoon until the nuts toast, about 4 to 5 minutes. Keep an eye on them as they can burn quickly!
Once the pasta is finished cooking, reserve ½ cup of the starchy water. Drain the spaghetti and add it to the skillet with the brussels and kale. Toss well. Stir in the parmesan cheese. Add in the reserve starchy water and toss. Taste and season additionally if needed.
Sprinkle the toasted pine nuts into the skillet and top with extra parmesan if you wish. Serve immediately!