Make the dressing. In a sealable jar, combine the lemon juice, salt, pepper, oregano, nutritional yeast, water, agave nectar, Dijon, garlic, and olive oil. Secure the lid and shake the jar vigorously to combine. Check the dressing for seasoning and adjust if necessary. Set aside.
Preheat your grill to high. In a medium bowl, toss the large broccoli florets with some olive oil, salt, and pepper. Once evenly coated, transfer florets to the grill and close the lid. Let the pieces char on one side for about 3 minutes. Carefully flip them over and let them char on the other side for another 2-3 minutes. Once the florets are evenly charred, transfer them back to the bowl and cover with a pot lid or dinner plate, allowing the broccoli to steam for 5 minutes.
Roughly chop the grilled and steamed broccoli and add it to the bowl with the pasta. To the bowl, also add the chickpeas, red onion, olives, pepperoncini, basil, and the crumbled vegan cheese (if using). Season the pasta salad with lots of salt and pepper. Pour the lemony oregano dressing on top. Toss everything to combine. Grab a fork and have a taste to check for seasoning. Adjust if necessary, toss one more time, and serve!
This grilled broccoli and pepperoncini pasta salad will keep in a sealed container in the fridge for up to 5 days. If you’re bringing it to a gathering and want to make ahead, I’d combine all of it except for the basil and vegan cheese. Toss those in at the last minute to keep everything looking vibrant!