Finely chop the onion into small pieces (about 3–4 mm) so it melts into the meat. Mince the garlic for deeper flavor. Chop the fresh chili finely (or measure out chili flakes) depending on your heat preference.
Roughly chop fresh herbs (basil, parsley, or cilantro) for your Green Goddess Dip. Halve the avocado, remove the pit, and scoop out the flesh. Squeeze a little lemon over it to prevent browning.
In a small bowl, mix breadcrumbs with milk to form a paste. In a large bowl, combine the lamb, onion, garlic, chili, spices, egg, and the breadcrumb paste. Use your hands to mix gently fold and press just enough to combine. Don’t over mix; it can make the meatballs dense.
Scoop small portions (1.5 to 2 tablespoons) and roll them into even rounds between your palms. Place each one on a plate or tray. Cover and refrigerate the meatballs for 15–20 minutes; this allows the binder to set and prevents them from falling apart in the pan.
Place a heavy skillet or non-stick pan on medium heat. Add 1 tablespoon olive oil and let it warm until it shimmers that’s your cue that it’s ready. If the oil smokes heavily, lower the heat slightly before adding the meatballs.
Add the meatballs in batches, leaving a little space between each. Don’t crowd the pan. Sear without moving them for about 2–3 minutes you should hear a steady sizzle and see a golden crust forming. Gently turn them with tongs or a spoon and cook for another 4–5 minutes, rotating to brown all sides evenly.
While the meatballs cook, combine avocado, Greek yogurt, garlic, fresh herbs, lemon juice, salt, and pepper in a blender or food processor. Blend until smooth and creamy.
Arrange the meatballs on a plate or shallow serving bowl. Spoon or drizzle the Green Goddess Dip on the side. Garnish with fresh herbs, chili flakes, or a squeeze of lemon for brightness.