Preheat the oven to 400ºF and line a large baking sheet with parchment paper.
Dice the eggplant into bite-sized cubes and toss them onto the baking sheet (even rows aren't necessary, just make sure they're spread out far enough so they're not touching).
Drizzle the eggplant with olive oil and sprinkle with salt and fresh cracked black pepper. Roast the eggplant for 20 to 25 minutes, rotating the baking sheet half-way through the roasting time.
Make the arrabiata sauce by heating a large pan over medium heat. Add 2 tablespoons olive oil, then add the minced garlic and cook for 3 minutes until it's golden. Add the crushed tomatoes and red pepper flakes.
Bring the sauce to a simmer and let it cook for 20 minutes. Season it with salt and pepper to taste.
Make the pasta according to package directions.
Once the eggplant is done roasting, add it to the arrabiata sauce, tossing to coat.
Spoon the eggplant arrabiata sauce over a bowl of pasta and serve.
You may have to simmer your sauce longer depending on the amount of liquid in your crushed tomatoes. I prefer the San Marzano brand because the tomatoes come in their natural, thick pureé rather than water, which dilutes the sauce.
You can up the crushed red pepper flakes to 1½ or even 2 teaspoons if you like more of a kick.