Beat the egg in a large mixing bowl. Add the ground turkey, panko bread crumbs, garlic, oregano, salt, paprika, and pepper. Mix everything up just so the ingredients are combined—avoid over-mixing, which can make the meatballs tough.

Roll the mixture into balls, about 1.5 heaping Tablespoons or 40g each. Place all rolled meatballs on a large baking sheet.

Place the onion slices in the bottom of the slow cooker, then top with half of the BBQ sauce and half of the Italian dressing (the rest will go on top).

Coat a large skillet with the olive oil and bring to medium-high heat. Lightly brown the meatballs in batches for about 1 minute on each side. (Do not skip this step! Locks in the flavor and helps set the shape so the meatballs do not fall apart.) Layer the meatballs into the slow cooker as you’re browning each batch. Once all browned meatballs have been added to the slow cooker, pour the remaining BBQ sauce and Italian dressing on top.

Cover and cook on low for 5 hours or on high for 3 hours. Serve warm with sauce and onions.

Store leftovers covered tightly in the refrigerator for up to 1 week.