Preheat oven to 400 degrees. Prepare a baking pan by lining with foil and spraying or drizzling with a bit of olive oil.
Combine all ingredients in a medium bowl and stir to distribute spices. Using an ice cream scoop, create even-sized meatballs and place on oiled baking pan.
Bake for about 16-18 minutes or until meat is no longer pink in the middle and cooked the way through.
Keep warm until ready to serve.
For Flatbread:
Heat a heavy skillet or a grill pan to medium-high heat. In a medium bowl {or in the bowl of a food processor while pulsing} combine all ingredients with a silicone spatula.
When the dough looks shaggy, knead it together until a ball forms. Divide dough into 4 equal pieces.
On a floured surface, roll out each piece of dough into a circular flatbread. Spray heated pan or skillet with a bit of olive oil or non-stick cooking spray and cook flatbreads until slightly puffed and starting to char in places, about 3-4 minutes on each side.
Keep warm until ready to serve.
For Yogurt Sauce:
In a small bowl, stir together all ingredients until well combined. Set aside until ready to use.
To Assemble:
Spread about a tablespoon of yogurt sauce on each flatbread. Sprinkle with spinach, tomato, and grated cucumber or zucchini. Place 2 meatballs on top of each flatbread and fold over into a "baco". You may need a toothpick to secure unless you plan on diving right in!