Prepare a rimmed baking sheet by pouring a bit of oil (I prefer canola, avocado, or olive) on. Cover the bottom by painting the oil across with a pastry brush.
Chop the veggies into roughly the same size pieces. Go for about 1/4 inch to 1 inch in thickness.
Lay the veggies in a single layer on the oiled sheet. Spread out as much as possible. If the veggies are crowded, use two baking sheets.
Sprinkle with all-purpose roasted veggie seasoning (see recipe below).
Bake for 15-30 minutes. Time will depend on which veggies you choose and how thick your veggies are.
Veggies are done when they start to char. It's VERY IMPORTANT to allow the veggies to char slightly for maximum flavour development.
Notes
Nutrition Information was calculated using asparagus.