Slice and dice the mushrooms, parsley, and garlic.
Over low to medium heat, add olive oil and saute the mushrooms and meat (ground beef, diced lean pork, or tuna) for three minutes
Add the tomato, parsley, and garlic and stir for two minutes.
Add the rice and saffron and stir for a minute.
Meanwhile, cut the top of the peppers open and clean them, ensuring there are no seeds or annoying pepper fibers left inside.
Fill the peppers without pressing.
Wrap them in foil and bake them in the oven at 356ºF or 180ºC for an hour.
Baking time will depend on the size of the peppers. I used large peppers in the photos, so it took me 1.5 hours. I recommend using smaller peppers and one hour of baking time.
Carefully unwrap one of the peppers, cut it open, and taste the rice grains at the bottom to ensure everything is well cooked. Put it back in the oven if necessary.
Serve and enjoy!