Preheat the oven 350F. Line a sheet pan with parchment paper.
In a large bowl combine ground turkey, oats, 2 tablespoons enchilada sauce, scallions, corn, beans, green chiles, garlic, egg, salt, cumin and onion powder.
Combine everything well using clean hands, then shape onto the sheet pan into an oval loaf flattened on top so you can add the sauce and cheese later.
Bake 55 to 60 minutes, until cooked through.
Remove from oven and top with the remaining enchilada sauce, cheese, and, jalapeño.
Bake until the sauce is heated through and the cheese is melted, about 5 to 10 minutes. Garnish with cilantro if desired. To serve, transfer to a cutting board and slice into 12 slices.