Preheat oven to 375 F.
Spray a baking pan with non-stick spray, and spread the broccoli, mushrooms, and bell pepper in single layer. Toss with salt, pepper, and olive oil. Push the veggies to one side of the baking pan.
Now, add the roasted red peppers to the other side. Sprinkle with salt and pepper.
Cook in the oven for 35-40 minutes, flipping halfway through.
Remove the roasted red peppers from the oven, and allow them to cool slightly.
Place all of the roasted red pepper sauce ingredients in a food processor and blend until smooth.
Place the olive oil and butter in a sauce pan over medium heat.
Once the butter is melted, add the garlic and cook for 1 minute, until fragrant.
Scoop the tomato paste into the pan and cook for another 1-2 minutes, using your spoon to break up the paste and cook it a bit.
Pour in the roasted red pepper sauce. Stir the sauce so it's smooth, and bring to a simmer, about 2-3 minutes. The sauce will thicken.
Add in the cooked rotini pasta and toss until it's coated in the sauce.
Finally, add the roasted veggies and give it a quick stir to incorporate the pasta, sauce, and veggies together.