In a small bowl, mix together salt, black pepper, garlic powder, onion powder, smoked paprika, and chili powder. Rub the spice mixture all over the brisket, pork shoulder, and chicken thighs.

Marinate (Optional)

If time permits, cover the seasoned meats and let them marinate in the refrigerator for at least 1 hour or overnight for deeper flavor.

Cooking

Preheat the Oven

Preheat your oven to 300°F (150°C).

Sear the Meats

In a large skillet, heat olive oil over medium-high heat. Sear the brisket and pork shoulder for 3-4 minutes on each side until browned. Remove from skillet.

Prepare the Vegetables (Optional)

Chop the onion, bell pepper, and garlic cloves. Add them to the skillet and sauté for 2-3 minutes until soft.

Bake the Meats

In a large oven-safe dish, place the seared brisket, pork shoulder, and chicken thighs. Add the sautéed vegetables on top. Cover with aluminum foil and bake in the preheated oven for 3-4 hours until the meats are tender.

Rest and Serve

Once cooked, remove the meats from the oven and let them rest for 15 minutes. Slice and serve them warm.