Prep the mushrooms. Wipe the caps clean with a damp towel. Twist out the stems and use a small spoon to gently scoop a bit more from the center to create space for filling. Finely chop the stems and set aside.

Pre-bake the caps. Heat the oven to 400°F (200°C). Brush the mushroom caps with 1 tablespoon oil, season with a pinch of salt and pepper, and place hollow-side up on a lined baking sheet. Bake for 8–10 minutes to release excess moisture. Drain any liquid from the pan and blot the caps with paper towels.

Cook the turkey filling. While the caps bake, warm the remaining oil in a large skillet over medium heat. Add onion and chopped mushroom stems. Sauté 3–4 minutes until softened. Add garlic and cook 30 seconds until fragrant.

Brown the turkey. Add ground turkey, breaking it up with a spatula. Cook until no longer pink, about 5–7 minutes. Season with taco seasoning, cumin, smoked paprika, chili powder if using, and a pinch of salt and pepper.

Build the sauce. Stir in tomato paste and broth. Simmer 2–3 minutes, stirring, until most of the liquid reduces and the mixture looks saucy, not wet. Taste and adjust seasoning. Stir in half the cilantro.

Stuff the mushrooms. Fill each pre-baked cap generously with the turkey mixture. Top with shredded cheese.

Bake until melty. Return to the oven for 6–8 minutes, or until the cheese is melted and the mushrooms are tender but still hold their shape.

Finish and serve. Top with remaining cilantro and a squeeze of lime. Add optional toppings like avocado, jalapeños, or a dollop of sour cream. Serve hot.