Place diced onion in a large mixing bowl, and stir in basil, salt-free all purpose seasoning, and garlic powder. Set aside.
Bring 2 cups water to a boil in a large pot.
Meanwhile, begin cooking ground beef over medium heat.
When the beef is fully browned, remove it from the pan and let it sit in a bowl with paper towels to absorb the extra fat.
The water should be boiling by now. Add the quinoa to the water.
Reduce the heat, cover, and let simmer for about 15 minutes.
While the quinoa is simmering, prep the pepper halves by cutting them in half, removing the stems, and scooping out the remaining seeds and membrane with a spoon. Set peppers aside.
Remove the ground beef from its bowl (blot with more paper towels if needed) and add it to the bowl with the onions. Stir to combine.
Stir in the can of tomatoes and salt.
When the quinoa is done, add it to the bowl and stir. It can be a bit clumpy, so make sure to mix it well.
Taste the filling and adjust seasonings if needed.
Use a spoon to fill each pepper half with filling.
Line peppers up in a baking dish.
Top each pepper with cheese.
Fill the dish with a little bit of water (enough to cover the bottom of the pan).
Cover with foil and cook for about 20 minutes (15 minutes for convection).
Remove foil and cook until cheese begins to brown, about another 10 minutes.
This recipe is in my blog’s gluten free category, but check the all-purpose seasoning you’re using to make sure it’s gluten free. If it’s not, substitute your preferred combo of any of the following: oregano, thyme, parsley, celery seed, paprika).