In a large bowl, combine Grass Run Farms ground beef with egg, salt, pepper, garlic powder, Parmesan cheese, and chopped basil until thoroughly mixed.
Take a golf-ball sized amount of the beef mixture and roll into a ball. Repeat with the rest of the beef mixture until you have 24 meatballs. Set aside on a separate plate.
Heat canola oil in a pan on high heat. Sear meatballs on one side for about one to two minutes. Flip. Cook for another one to two minutes. Remove meatballs from pan and drain.
Pour marinara sauce into pan and place meatballs into sauce. Cook for about eight to ten minutes, flipping meatballs in sauce until reduced to a thick consistency. Remove from heat.
Cut dinner rolls in half, lengthwise. Arrange the bottom half into a baking pan.
Place one meatball on each bottom roll layer. Lay mozzarella cheese slices evenly on top. Cover with the top half of the dinner rolls.
In a small bowl, combine the melted butter, garlic, basil, and Parmesan cheese, stirring until evenly mixed. Pour the garlic butter mixture over the top of the assembled sliders.
Bake for 20 minutes until the rolls are golden brown and cheese is melted.