Veg Burger Advice, Am i missing something?
To get crunchy buns, you can toast them in an oven beforehand. Here is how I do it:
Take the bun out of the package, slice it open and put it in a preheated oven (180C / 350F) for about 5-8 minutes. Keep an eye on them!

Depending on the brand and model, you could also put the bun halves in a toaster.

Then assemble your burger however you like. I would not fry it afterwards.