Step 1

Grate the onion using the large holes of a box grater over a large bowl. You should end up with about ¼ cup.

Step 2

Chop the spinach and basil into very small pieces. Alternatively you can add the onion, basil, and spinach to a food processor and pulse until finely chopped but not pureed.

Step 3

To the same bowl, add the nutritional yeast, garlic powder, and salt, stirring to combine. Add the turkey and stir again, until all the ingredients are well incorporated.

Step 4

Add the olive oil to the base of a 6-quart slow cooker, spreading it around until the bottom is well coated.

Step 5

Using a small, 1.6-inch cookie scoop, scoop the turkey mixture into a single layer into the base of the slow cooker. Gentle scoop any remaining mixture on top, creating a second layer. If you don’t have a cookie scoop, you can use a large soup spoon instead. Ground turkey is very sticky, so trying to roll them into balls by hand will likely result in a mess, so use the scoop or spoon method for best results.

Step 6

Pour the marinara sauce over the meatballs. Do not stir.

Step 7

Cover and cook on high for 4 hours or low for 6-Uncover and gently stir to separate the meatballs.

Step 8

Serve over pasta, spaghetti squash, or with crusty bread, topped with fresh basil, parmesan (traditional or dairy-free), and red pepper flakes if desired.