In a small bowl, combine onion powder, garlic powder, cumin, paprika, oregano, and cayenne pepper. Mix well.

In a medium saucepan, heat olive oil over medium heat. Add flour and stir to form a paste, cooking for about 2 minutes.

Whisk in chicken stock and tomato passata, along with half of the spice mix. Let simmer for 10 minutes.

In a large skillet, heat olive oil over medium heat. Sauté finely chopped onion until translucent, then add ground beef and cook until browned.

Add remaining spice mix, refried beans, and black beans. Stir until well mixed and heated.

Spread a layer of sauce on the bottom of a baking dish, fill tortillas with meat mixture, roll and place seam-side down.

Preheat oven to 350°F (175°C). Pour remaining sauce over enchiladas and sprinkle with cheese. Bake covered for 10 minutes, then uncover for another 10 minutes.

Garnish with cilantro, sour cream, or hot sauce. Serve with Mexican rice or avocado salad.