12 ounces tomato-based chili sauce (like Heinz brand) or barbecue sauce
10 ounces grape jelly
1 tablespoon to 2 tablespoons lemon juice
2 tablespoons extra-virgin olive oil
1 pound ground beef (15 to 20 percent fat)
2 large shallots, finely chopped
2 cloves garlic, grated
1/2 cup Panko bread crumbs
1/2 cup fresh parsley, roughly chopped
1 egg, lightly beaten
2 teaspoons kosher salt, plus more if needed
1/2 teaspoon red pepper flakes
  1. In the bowl of a slow-cooker (at least 5 quarts) whisk together chili or barbecue sauce and grape jelly. Place the lid on the slow-cooker and cook on high for 15 minutes. Remove the lid and whisk until smooth. Stir in 1 tablespoon lemon juice.
  2. Meanwhile, preheat the oven to 425 degrees Fahrenheit and drizzle olive oil over a sheet pan. In a large bowl, combine beef, onion, garlic, Panko, egg, salt and red pepper flakes until just combined. Form into 20 to 22 scant 1-inch meatballs. (If you have a little over 1 pound meat, make meatballs ever so slightly smaller and make another one or two; the idea is that these are one- or two-bite meatballs so smaller is okay.)
  3. Place meatballs on the prepared sheet pan and bake, shaking the pan halfway through, until browned, 10 minutes.
  4. Transfer warm meatballs to the slow-cooker with the sauce. Gently toss meatballs in sauce to coat. Place the lid on the slow-cooker and cook, tossing halfway through, on high for 1 to 2 hours, or low for 3 to 4 hours. Taste, and stir in another tablespoon lemon juice mixed with a pinch of kosher salt if you find the sauce a bit too sweet. Serve warm with toothpicks.