While your oven preheats to 450°F, prepare all your vegetables: chop the broccoli into bite-sized florets, dice the bell pepper, cube the cucumber, and measure out the coleslaw mix. Having everything prepped and ready will let you assemble quickly once the chicken and pasta are done cooking. Start a large pot of salted water boiling for the pasta—you'll need it ready in just a few minutes.
Pat the chicken breasts dry with paper towels, then coat lightly with olive oil on both sides. In a small bowl, combine the garlic powder, paprika, salt, black pepper, and dried oregano, then rub this mixture evenly over both chicken breasts. Place on a baking sheet and bake at 450°F for 18-22 minutes until the internal temperature reaches 165°F. The chicken will finish cooking while you prepare the other components.
Add the chickpea pasta to your boiling water and cook according to package directions until al dente—aim for firm texture rather than soft. Drain the pasta in a colander and rinse briefly with cold water to stop the cooking process and cool it slightly. Set aside in a large bowl to cool further while you prepare the dressing.
In a medium bowl, whisk together the Greek yogurt, mayonnaise, and Dijon mustard until smooth and well combined. Add the fresh lemon juice, chopped dill, water, garlic powder, onion powder, salt, black pepper, and maple syrup. Whisk everything together until you have a creamy, pourable dressing with visible flecks of dill throughout. I like to taste a small spoonful at this point and adjust the seasoning—a touch more lemon juice brightens it up beautifully if needed.
Remove the chicken from the oven and let it rest for 5 minutes—this keeps it juicy and makes it easier to shred. Once cooled slightly, use two forks or your hands to shred the chicken into bite-sized pieces. You should have roughly 2-2.5 cups of shredded chicken ready to add to the salad.
In your large bowl with the cooled pasta, add the shredded chicken from Step 5, all the prepped vegetables from Step 1, the coleslaw mix, and the nutritional yeast. Toss gently to distribute everything evenly. Pour the ranch dressing from Step 4 over the top and toss again until every component is well coated with dressing. I find that letting it sit for 10-15 minutes before serving helps all the flavors meld together beautifully.
Divide the pasta salad into bowls or plates and serve immediately. The salad can also be refrigerated for up to 3 days—just give it a quick stir and add a splash of water if the dressing seems too thick after sitting.