Heat 1 tablespoon olive oil in a large skillet over medium heat. Add butternut squash and stir to coat. Sprinkle with salt, pepper and chili powder. Continue to cook over medium heat until squash is a nice golden brown and starting to caramelize just a bit (but not mushy), stirring frequently to prevent burning. Carefully remove to a plate and set aside.
Meanwhile, in a separate pot, warm up vegetable (or chicken) stock and keep warm.
To the same skillet (that the butternut squash was cooked in) add the onion and sauté for 3-4 minutes over medium heat, stirring frequently. Add the minced garlic to the onion and cook for an additional minute before stirring in the arborio rice. Sauté the rice with the onion and garlic for 1-2 minutes, stirring to prevent browning. Add the white wine and cook, stirring continuously, until at least half of the liquid has been reduced.
Reduce heat to medium-low and gently stir in the warm vegetable broth with the rice, 1 cup at a time. Gently stir and mix in the broth with the rice as it is being added. Once the liquid is absorbed into the rice, add an additional 1 cup of broth to the rice. Continue with this method until rice reaches desired consistency- it should be done, but still have a bit of firmness left to it (in other words, el dente). I ended up using 4 full cups of broth.
Stir in half and half, salt and pepper (to taste), dried thyme, shredded cheese and chopped kale. Mix well. If it seems to thick, add an additional 1/2 cup warm broth and gently mix to combine. Cook on low until kale is cooked and seasoning has been adjusted to your preference. Gently stir in the cook squash and garnish with additional red chili flakes or Parmesan cheese and fresh lemon juice.
Serve immediately (although leftovers are also fantastic).