Mix the powdered buttermilk, kosher salt, onion powder, and Parmesan together in a medium sized bowl.
Place vegetables (one kind at a time) onto a parchment lined microwave safe plate and spray with oil. Sprinkle seasonings over vegetables.
Microwave on high for 4-6 minutes or until the veggies have started to brown. Wait until they brown a little or they will not crisp up, but be careful not to over- brown or burn. Repeat with each vegetable until all have been cooked.
These can be eaten right away or stored for a day in an air tight container.