Preheat your oven to 350°F.
While the rice is cooking, heat the olive oil for the enchiladas in a large skillet over medium-high.
Add the onions and cook until soft and translucent, about 5 minutes.
Add the ground beef, mushrooms, and the remaining half of the spice mixture.
Cook the beef and mushrooms, breaking up the beef as it cooks, until it's no longer pink in the center, about 5-7 minutes.
Warm the tortillas in a skillet over medium heat for about 15 seconds each.
Fill the tortillas with the beef mixture, tuck in the sides, roll closed and place on top of the rice in the casserole dish.
Top the filled tortillas with the enchilada sauce and cheese.
Bake for 20-25 minutes, or until the cheese is melted and sauce is hot and bubbly.