In a pan, heat the olive oil and cook the onion for 5 minutes. Add in the chili powder and oregano and stir until combined.
Add in the ground plant-based meat and salt and pepper. Cook for a few minutes, then add the kale, tomatoes, and rice too.
Preheat oven to 375F. Cook the filling mixture for a few more minutes and taste for seasonings, then press the mixture into the peppers until they are fully packed right to the top. Stand them upright in a glass baking dish that has been coated with some olive oil.
Bake for about 30 minutes. Cover with foil if starting to get too brown on top. Enjoy hot from the oven as a complete meal.