Preheat your oven to 430°F (220°C). Toss diced sweet potatoes and minced garlic with olive oil, salt, and pepper. Spread on a baking sheet and roast for 20-25 minutes until tender and lightly caramelized.

In a large pot, bring salted water to a boil. Add short pasta and cook according to package instructions until al dente, about 8-10 minutes. Reserve 2/3 cup of pasta water, then drain.

Heat a skillet with olive oil and unsalted butter over medium heat. Fry the fresh sage leaves for 2-3 minutes until crispy, then remove and drain on a paper towel.

Return the skillet to the heat and add half of the roasted sweet potatoes. Mash gently, leaving some chunks for texture. Stir in the minced garlic and remaining sweet potatoes.

Add the drained pasta to the skillet with the sweet potato mixture. Pour in the heavy cream and crumble in the goat cheese, adding some reserved pasta water. Stir over medium heat for 2-3 minutes until creamy.

Adjust seasoning with salt and black pepper. Serve the pasta and top with crispy sage leaves, a drizzle of olive oil, grated Parmesan cheese, and crushed red pepper flakes.