Season the sliced brussel sprouts by tossing gently in a medium bowl with salt and pepper. Remove and do the same with the sliced tomatoes.
Line a baking sheet with parchment paper, and spread out the brussel sprouts, cut side down. Place in the oven and set the timer for 12-15 minutes. (Cooking time will vary depending on the size of your brussel sprouts.)
Line a second baking sheet with parchment paper, and spread out the tomatoes, cut side up. When the timer goes off for the brussel sprouts, place the tomatoes in the oven. Remove the brussel sprouts and turn them over, then place them back in the oven with the tomatoes, and cook both together for another 15 minutes or until the the vegetables are browned and the brussel sprouts are just tender.
Cook the pasta, drain, and return it to the pan. Toss the pesto and pasta together over low heat, just enough to warm through.
Place the cooked brussel sprouts and tomatoes in a medium bowl, and gently toss together with the balsamic vinegar.
To assemble, place the pesto pasta in serving dishes, and top with the tomatoes and brussel sprouts. (You could simply toss it all together, but I think it looks prettier this way, and the tomatoes won't get mushy.)
If desired, garnish with reserved basil, crushed red pepper flakes and cashew parmesan.
To make it faster: Get your veggies roasting first, then make your pesto sauce (if making your own) and cook your pasta. To save even more time, swap the brussels sprouts for quicker cooking asparagus (15 minutes) or more cherry tomatoes. To make it your own: Change up the veggies to whatever you like best! Just make sure to choose ingredients that cook together at the same temperature and be mindful of any variations in cooking times. To make it pasta salad: Chill it! You can also add ingredients like kalamata olives, slivered red onions and ribbons of fresh basil.