Make sure to carefully follow each step of the instructions for the best results :
Prep the mushrooms:
Preheat the oven to 400°F. Remove the stems from the portobello mushrooms and gently scrape out the gills if desired. Brush the caps with olive oil and season with salt and pepper, then place them open side up on a baking sheet. Many stuffed portobello recipes start by cleaning and pre-baking or prepping the caps so they hold the filling better.Cook the turkey filling:
Heat olive oil in a skillet over medium heat. Add the onion and cook for a few minutes until softened, then stir in the garlic and ground turkey. Cook until the turkey is browned and no longer pink, breaking it up with a spoon as it cooks. Browning the turkey with onion and garlic is the base method used across many versions.Add the vegetables and seasoning:
Stir in the spinach, tomatoes, Italian seasoning, paprika, salt, and black pepper. Cook for another 2 to 3 minutes until the spinach wilts and the filling comes together. Similar recipes often use spinach, tomatoes, peppers, or herbs to build out the filling.Stuff the mushrooms:
Divide the turkey mixture evenly among the mushroom caps. Top with cheese if using. Stuffed portobello recipes often finish with a little cheese or herbs before baking, though cheese can be skipped if you want a lighter version.Bake and serve:
Bake for 12 to 15 minutes, until the mushrooms are tender and the filling is hot. Finish with chopped parsley or basil and serve warm. Most versions finish the stuffed mushrooms in the oven until the caps soften and the filling sets nicely.