Step 1

Purée red peppers, chile, garlic, oil, vinegar, salt, and paprika in a blender until very smooth. Transfer to a small bowl.

Step 2

Do Ahead: Sauce can be made 1 day ahead. Cover and chill.

Step 3

Place a rack in upper third of oven; preheat to 450°. Mix panko, 2 Tbsp. piri-piri sauce, and 1 Tbsp. water with a fork in a medium bowl to hydrate panko. Add egg and mash together with fork until paste is homogenous, about 1 minute. Let sit until panko is softened, about 3 minutes. Add garlic, salt, cumin, paprika, and 1 Tbsp. oil and stir to incorporate. Add about one-third of ground beef and gently work into panko mixture with your hands until it no longer feels wet and is well incorporated. Add remaining ground beef and gently combine again with your hands until evenly dispersed and homogenous.

Step 4

Form ground beef mixture into twelve 2"-diameter balls. Space evenly on a foil-lined rimmed baking sheet.

Step 5

Bake meatballs 5 minutes, then turn on broiler (you can leave the meatballs in the oven while broiler heats up) and broil until golden brown on top and just barely cooked through, 5–6 minutes longer.

Step 6

Spread yogurt among plates. Arrange meatballs on top. Drizzle with remaining piri-piri sauce and more oil.