I like a good bowl meal. The template is grain/pseudo-grain, legume, two or three veggies, sauce. So you could have a quinoa and chickpea bowl with pickled red onions, kale, and roasted red peppers, topped with a hummus tahini sauce. Or a black bean and rice bowl with pickled jalapeños, grilled corn (which is also technically a grain but it still works as a vegetable) and chopped red tomatoes, with an avocado crema sauce. It's extremely flexible, easy to make, and good for meal prepping. You can add an additional protein if it's still not filling enough, like fried tofu or crumbled tempeh or seitan "chicken".

It's far from the only way to make an easy, filling veggie meal, but it's one of the easiest frameworks for people used to the "meat, carb, vegetable side dish" style of meal.