I regularly make vegetable enchiladas. My favorite combo is cauliflower, butternut squash, and mushrooms.
Get a can of enchilada sauce. Get a bag of flour tortillas. Get a block of jack or cheddar cheese, or use a combo, and shred about 2 cups. You will also need a small can of diced green chilies.
Peel and dice a small butternut squash. Cut up a small (or half of a large) cauliflower into bite sized pieces. Chop up a pint container of white mushrooms into quarters. Chop up about a half a cup of onions.
Preheat your oven to 425 degrees. Use cooking spray on a baking dish (glass, metal, ceramic, or foil) that will hold 6 to 8 rolled up enchiladas.
In a large frying pan, use about 2 Tablespoons of olive oil to sauté your onions, then add the cauliflower and butternut squash until just barely fork tender, then add the mushrooms until just browned. You don’t want to completely cook the veggies, as they will continue to cook in the oven.
Divide up the veggie mixture (in your mind) so that you have an equal amount to fill 6 to 8 medium sized tortillas.
Pour enough enchilada sauce to just cover the bottom of your baking pan. Then load the sateed veggies, a bit of the canned diced green chilies, and some shredded cheese into each tortilla, and roll them up, and place them into the baking pan, seam side down so they don’t open up.
After they are all rolled up in the pan, pour the remaining sauce over and around the rolled up tortillas. Then cover with shredded cheese, and bake at 425 degrees for about 15 minutes. Then serve.
It should look something like this: https://food.fnr.sndimg.com/content/dam/images/food/fullset/2007/4/30/0/Cinco_Enchiladas.jpg.rend.hgtvcom.826.620.suffix/1382538528797.jpeg
You can also add chopped olives, or shredded rotisserie chicken, or cooked canned chicken if you like. Then you can top with fresh salsa, avocado, or sour cream if you like after they come out of the oven.
Add refried beans and Spanish rice if you like, and you’ve got a meal, and a party.