In a medium bowl add the ingredients: ground beef through ground pepper and mix just until combined. Use a large hinged scoop, or a spoon and make meatballs about 2 1/2 inches in circumference. Place on a parchment lined plate and continue with remaining meat mixture.
Grill the meatballs for about 15 minutes or until no longer pink inside, turning every few minutes to cook on each side. Toast the bagel halves for 1 minute on the grill. Remove and assemble by placing a meatball on 8 of the bagels, spread a tablespoon of greek yogurt dip on the bagel top and press onto the meatballs. Use a toothpick to hold them in place (optional). Serve immediately.
Recipe by Farmgirl Gourmet at http://www.farmgirlgourmet.com/2014/11/moroccan-meatball-sliders.html