Line the slow cooker with aluminum foil and set aside.
In a medium bowl, combine the ground beef, sausage, onion, garlic, egg, bread crumbs, tomato paste, Italian seasoning, Worcestershire sauce, salt and pepper until well blended. DO NOT OVER MIX.
Place the meatloaf mixture in the slow cooker and shape into an oval loaf shape (or round if your crockpot is round).
In a small bowl, whisk together the ketchup, brown sugar, vinegar and mustard.
Spoon half the glaze over the meatloaf to coat.
Place the lid on the slow cooker and cook for 3-4 hours on high or 6-7 hours on low. Check for doneness with an instant read thermometer. The meatloaf is done when it registers 160 degrees F.
Using the foil, lift the meatloaf out of the slow cooker and place on a baking sheet.
Transfer the meatloaf to the oven and broil on high for 3-4 minutes until the glaze begins to caramelize.
Remove the meatloaf from the oven and allow to rest for 10 minutes.
Serve the meatloaf with the remaining glaze.
Video
Notes
Meatloaf Variations
Classic Ketchup Glaze: ½ cup ketchup + 2 Tbsp brown sugar + 1 Tbsp Dijon + 1 tsp Worcestershire.
BBQ Glaze: ½ cup BBQ sauce + 1 Tbsp ketchup + 1 tsp apple cider vinegar.
Balsamic-Dijon (house favorite): ⅓ cup ketchup + 2 Tbsp balsamic + 1 Tbsp Dijon + 1 Tbsp brown sugar.
Stuffing-Mix Meatloaf: Swap breadcrumbs for 1 cup crushed stuffing mix; reduce added salt.
French Onion: Stir in ½ envelope onion soup mix + ½ cup finely diced sautéed onions.
Italian-Style: Use Italian breadcrumbs; add 1 tsp Italian seasoning, 2 Tbsp grated Parmesan; glaze with marinara after cooking, then broil.
Bacon-Topped: Lay 4–6 half-slices of bacon over the shaped loaf. Cook as directed; glaze and broil to crisp the bacon.
Cheddar-Stuffed: Press loaf flat, scatter ¾–1 cup shredded cheddar, seal and reshape. Slice gently after resting.
Mushroom & Thyme: Fold in 1 cup finely chopped, sautéed mushrooms + ½ tsp thyme for steakhouse vibes.
Southwest: Add ½ tsp cumin + ½ tsp chili powder, fold in ½ cup corn and ¼ cup diced green chiles; finish with BBQ glaze.