Preheat the oven to 425ºF. Place the butternut squash cubes on a large baking sheet. Drizzle with oil, then add the smoked paprika, garlic powder, kosher salt, and pepper. Using your hands, toss the cubes to make sure all are covered. Spread them out in a single layer and roast for 25-30 minutes, flipping once halfway through.
While the butternut squash roasts, make the pasta and the romesco. For the pasta, bring a large pot of salted water to a boil and cook according to the directions on the package. Before draining the pasta, remove 1 cup of starchy water and set aside. Then drain and return to a serving bowl.
For the romesco, place the roasted red peppers, almonds, garlic, tomato paste, red wine vinegar, smoked paprika, and lemon juice in a blender or food processor. Pulse until a paste forms. Then slowly stream in the olive oil until a sauce forms but there's still some texture to it. Transfer the romesco to a small bowl and add the salt and pepper.
Add the romesco plus 1/4 cup of the starchy pasta water to the pasta. Toss vigorously to combine, adding more water if needed to loosen. Add in the butternut squash, reserving a few pieces for the top of the pasta to garnish. Once everything is combined, dot the top with feta and the remaining butternut squash. Sprinkle the sliced almonds and torn basil on top. Serve immediately. Enjoy!
