Step 1

Arrange a rack in the middle of the oven and heat the oven to 425°F. Coat a rimmed baking sheet with cooking spray or olive oil.

Step 2

Prepare the following, adding each to the same large bowl as you complete it: Thinly slice 4 medium scallions (about 2/3 cup). Pick the leaves from 1/2 large bunch fresh parsley until you have 1 cup, the leaves from 1/2 large bunch fresh cilantro until you have 1 cup, and the leaves from 1/2 medium bunch fresh mint until you have 1/2 cup. Mix all of the herbs together and reserve 1 cup for garnish. Add the remaining herbs to a blender and reserve the bowl.

Step 3

Cut 1/2 medium yellow onion into 1-inch chunks (about 1 cup). Add the onion, 2 large eggs, 4 peeled garlic cloves, 1 1/2 teaspoons kosher salt, and 1 teaspoon black pepper to the blender. Blend on high speed until the mixture is almost smooth, 20 to 45 seconds. Pour into the reserved bowl.

Step 4

Add 1 pound ground beef and 1 1/4 cups plain dried breadcrumbs and mix with your hands until everything is evenly combined. Scoop the mixture into 2 tablespoon-sized portions and roll into balls with lightly oiled hands. Arrange on the baking sheet, spacing them at least 1-inch apart.

Step 5

Bake for 8 minutes. Flip the meatballs (slide a thin spatula under them if they stick to loosen) and rotate the baking sheet. Continue baking until lightly browned, cooked through, and no longer pink in the center, 6 to 8 minutes more.

Step 6

Spread 1 1/2 cups Greek yogurt on a large serving bowl or plate. Transfer the meatballs on top of the yogurt and drizzle with olive oil. Garnish with the reserved herbs (tear any large leaves into bite-sized pieces).