1: Place bread in a small bowl and pour enough milk over to wet each piece.

Let soak for 5 minutes. Using your hands, gently wring out the excess liquid and place the bread into the bowl of a food processor.

2: Add ground beef and lamb, onion, garlic, egg yolk, herbs and spices to the food processor.

Add the zest of one lemon and the juice of half a lemon. Pulse the mixture on low until combined and slightly fluffy in texture.

3: Transfer the meatball mixture to a bowl, cover with a towel and let rest in the fridge for about an hour.

4: Heat up your oven for 15 to 20 minutes with the flames on high to allow the baking stone to get hot, aiming for around 750 °F (300 °C).

You can check this quickly, accurately and from a safe distance with an infrared thermometer.

5: Remove the meatball mixture from the fridge and form into 1-inch (2.5-centimeter) balls.

If the mixture is sticky, dampen your hands with water. Place meatballs on a baking sheet or plate.

6: Preheat a cast-iron skillet in your Ooni on high heat for 3 minutes.

Carefully remove the skillet from the oven with gloves on, then reduce the flames to low (aim for around 550 °F or 288 °C). 

7: If the skillet is smoking, allow it to cool down a moment, then coat the bottom of the pan with a thin layer of neutral oil.

Using tongs, arrange the meatballs in the cast iron skillet in an even layer.

8: Return the skillet to the oven and cook for 3 minutes.

Remove the skillet from the oven and rotate the meatballs for even browning using tongs. Rotate the skillet 180 degrees and return to the oven for an additional 3 minutes or until meatballs are browned on at least two sides. Drain meatballs on a paper towel.

9: Serve and enjoy with a side of tzatziki sauce, or use them on a Greek Mezze Pizza