Preheat oven to 400ºF and line a baking sheet with tin foil. Place tomatoes, onions, garlic, olive oil, 1/2 teaspoon salt, and pepper onto baking sheet and drizzle with 2 tablespoons olive oil. Toss, making sure everything is coated. Roast at 400ºF 20 minutes.

While vegetables are roasting, cook the pasta according to package’s instructions.

Remove baking sheet from oven, remove skin from tomatoes, and roast for an additional 10 minutes.

Next, transfer all ingredients on the baking sheet (including juices) into a blender along with soaked cashews and the remaining olive oil and salt. Blend until smooth.

Toss pasta with sauce and top with fresh basil and cracked pepper.