Preheat oven to 350 degrees. Spray 18 muffin tins with cooking spray.
In a medium bowl, stir together the brown sugar, ketchup, and Worcestershire sauce. Set aside.
In a large bowl, combine remaining ingredients until fully incorporated (I just used my hands to "knead" the ingredients into the ground beef).
Scoop ½ Tbsp of brown sugar sauce into bottom of each muffin tin, setting aside the remaining sauce.
Using a cookie scoop, scoop ground beef into balls, rolling them in your hands to make sure they'll stay together. Put each ball in a muffin tin.
Bake at 350 degrees for 20 minutes. Remove from oven, scoop 1 tsp of remaining sauce onto each meatball and set oven to broil. Set aside remaining sauce.
Bake meatballs for 3 minutes more. Remove from oven.
Microwave remaining sauce for about 40 seconds or until warm. Serve remaining sauce with meatballs and drizzle sauce from muffin cups onto meatballs if desired.
Recipe by Simple, Sweet & Savory at https://www.simplesweetsavory.com/baked-sweet-and-saucy-meatballs/