Prep. Cut all the veggies as directed and combine in a large bowl.
2 bell peppers, 1 medium zucchini, 1 yellow squash, 1 cup cherry or grape tomatoes, 1 or 2 medium onions
Season. Drizzle with olive oil, then sprinkle with Italian seasoning, salt, and pepper. Toss well and set aside for at least a few minutes while you gather your skewers and preheat the grill to medium-high, if cooking right away. (If possible, letting the veggies marinate for at least 20-30 minutes will enhance the flavor.)
1 and 1/2 Tablespoons extra-virgin olive oil, 1 Tablespoon Italian seasoning, 1 teaspoon kosher salt, 1/2 teaspoon black pepper
Assemble. Thread the veggies onto skewers, alternating as you go. Try to thread peppers and onions right down the middle, tomatoes with the skewer poking through the long way, and zucchini and squash with the skewer going through the skin so you can see the whole medallion, if that makes sense.
Grill. Place kabobs directly on the preheated grate (we aim to get it around 400°F) and cook for about 5 minutes on each side, roughly 10 minutes total, until they are tender and a little bit charred on the edges.
Serve. Remove skewers from the heat and serve as desired. Tent with foil if you want to keep the veggies warm while finishing up other things. If using metal skewers, in particular, be aware that the ends will be hot to the touch for several minutes!