Preheat your oven to 400ºF.
Heat the olive oil in a large skillet over medium-high heat. Once hot, add the ground turkey and cook for 3-4 minutes to brown one side before breaking apart to fully cook.
Once the turkey is fully cooked and no pink remains, add the frozen vegetables, black beans (undrained), and taco seasoning. Stir everything together and cook for 3-4 minutes until the onions and peppers have softened.
Turn off the heat and transfer half the mixture to a bowl. Place 3 corn tortillas on top of the remaining mixture in the skillet. Add half the enchilada sauce and spread evenly across the tortillas.
Add the remaining turkey mixture on top of the tortillas and top with the remaining 3 tortillas (place them in a different pattern than the original 3 to cover gaps), enchilada sauce, and shredded cheese.
Bake for 15-20 minutes until the cheese is golden brown. Garnish with cilantro or scallions, diced tomatoes or pico de gallo, and cotija cheese. Slice into 6 slices and serve warm.