Preheat your oven to 375°F. Lightly grease a 12-cup muffin tin.

In a small bowl, combine the breadcrumbs and milk, and let them soak for a few minutes while you prepare the vegetables.

Heat a small skillet over medium heat with the avocado oil. Add the finely chopped onion and red bell pepper and sauté for 3-5 minutes until softened and fragrant.

Stir in the minced garlic for the last 30 seconds of cooking, then remove the skillet from the heat and let the vegetables cool slightly.

In a large bowl, combine the ground beef, the soaked breadcrumbs (crumble them if they've clumped together), the sautéed vegetables, egg, 1 1/2 tablespoons ketchup, 1 tablespoon Worcestershire sauce, Italian seasoning, smoked paprika, salt, and pepper.

Mix gently with your hands until all ingredients are just combined and evenly distributed, being careful not to overmix.

Divide the meatloaf mixture evenly into the 12 greased muffin cups, pressing down gently to form a compact, rounded shape. A large cookie scoop can help with portioning.

In another small bowl, whisk together all the glaze ingredients (1/4 cup ketchup, brown sugar, yellow mustard, 1 teaspoon Worcestershire sauce, and garlic powder) until well combined.

Spoon a small amount of the glaze onto the top of each mini meatloaf and spread it into a thin, even layer.

Bake for 20-25 minutes, or until the mini meatloaves are fully cooked through and an instant-read thermometer inserted into the center of a meatloaf registers 165°F.

Let the mini meatloaves cool in the muffin tin for 5 minutes before carefully removing them. Serve warm, garnished with fresh parsley if desired.