I have tried a couple ways to do this and they have been OK. Of course, when I worked in industrial kitchens, using a deep fryer and a stainless steel potato masher (but larger) was ideal, but neither of these tools are available in my home kitchen.
So basically, I have a 12-15 inch flour tortilla I want to make into a fried bowl for a nice salad. Any ideas?
JustRightMenus touched on this topic in this answer to a similar question.
Quoting that answer:
you can make your own shell for taco salad by placing a large flour (burrito-size) tortilla in an oven-safe bowl (shaped however you'd like) and putting a big ball of tinfoil inside it. You can also do the opposite - place the bowl upside-down and drape the tortilla over it. Either way, Bake at 350 degrees for 10-15 minutes until it's lightly browned, and you're done! When you remove the tinfoil and the bowl, the tortilla will hold its own shape.
I've seen a posting somewhere that used a muffin pan, putting it upside down and placing smaller tortillas in between the crevices before baking. They look great, wavy, just like they serve in the restaurants!