Bring a pot of water to a boil.
Add pasta to the pot of boiling water and cook it according to the package’s instructions.
While it cooks, in a large sauté pan over medium heat, add 1 tablespoon of olive oil, a few pinches of sea salt, and the sweet potatoes. Cook, uncovered, for 5 minutes. Toss the sweet potatoes around with a wooden spoon, cover the sauté pan with a lid, and cook for 5 more minutes.
Place the pine nuts in a sauté pan over medium heat if using and toast them for 3 minutes, stirring frequently or shaking the pan until they’re golden.
Your pasta should be done around now, so drain it and return it to the pot.
Add garlic and kale to the sauté pan with the sweet potatoes, plus the red pepper flakes if using. Cook for 2 to 3 minutes, until the kale has wilted and turns bright green.
Remove from the stove and pour lemon juice over them.
Drizzle the remaining tablespoon of olive oil over the cooked pasta, add the sautéed vegetables and pine nuts, and toss. Season with salt to taste and sit down, take deep breaths, think happy thoughts, and serve warm, preferably with ginger tea or ginger kombucha on the side.