In a large bowl, combine the ground beef, ground chia seed, Italian seasoning, garlic powder, salt, and pepper. Mix to combine well. If your mixture is very dry, add a little water as needed. Roll into 36 meatballs.

In a large skillet, heat half of the butter or oil over medium heat. Add half the meatballs and brown on all sides. Transfer to a slow cooker. Repeat with the remaining butter and remaining meatballs. Pour the pan juices over the meatballs in the slow cooker.

Cook on low for 3 to 4 hours, until they reach an internal temperature of 160F. Keep warm in the slow cooker.

In a medium saucepan over medium heat, combine the frozen raspberries, minced chipotle, water, and apple cider vinegar. Bring to simmer and cook until the berries are soft enough to be mashed with a fork.

Transfer to a serving bowl. Serve with meatballs.