In a large mixing bowl, combine ground beef, minced garlic, finely chopped onions, breadcrumbs, baking soda, chopped fresh herbs, olive oil, salt, and pepper. Mix well and refrigerate for at least 2 hours.

Preheat your oven to 425°F (220°C). Form the meatball mixture into small balls and arrange them on a baking sheet lined with parchment paper. Bake for 30-40 minutes, turning halfway, until golden brown.

Wash and cut the medium potatoes into wedges. Toss them with olive oil, cumin, paprika, oregano, salt, and pepper. Roast in the oven while meatballs are cooking until golden and crispy.

In a medium bowl, combine Greek yogurt, grated cucumber, minced garlic, lemon juice, chopped dill or mint, and salt. Stir until creamy and chill.

Assemble the bowls with a bed of lettuce, topped with tomatoes, cucumbers, red onion, kalamata olives, roasted potatoes, meatballs, and tzatziki sauce.