Melt butter with olive oil in a saucepan over medium heat. Add onion and salt; cook and stir until onion starts to turn golden brown, 3 to 5 minutes. Stir in flour, chile powder, cumin, chipotle powder, black pepper, oregano, cayenne, and cinnamon. Cook and stir until fragrant, about 3 minutes. Add minced garlic and tomato paste; stir until fully combined. Pour in chicken broth and whisk until smooth.

Increase heat to high and bring sauce to a simmer. Reduce heat to medium-low and simmer, stirring occasionally, until flavors come together, about 10 minutes. Taste and season as desired. Blend sauce with an immersion blender.

Preheat the oven to 400 degrees F (200 degrees C).

Lightly brush tortillas with oil. Heat a small cast iron skillet over medium-high heat. Heat tortillas until flexible, about 30 seconds per side.

Cover the bottom of the skillet with a scoop of enchilada sauce. Place a tortilla on top and add 1/2 of the chicken, 1/3 of the Jack cheese, and 1/2 the cilantro and green onions. Spoon on more sauce and repeat layers, finishing with sauce and the remaining cheese.

Bake in the preheated oven until cheese melts and sauce is bubbling, 10 to 15 minutes.