Remove the tenderloins of chicken (if any, and keep for another dish). Slice each breast into two even pieces. Score in criss cross fashion the thickest parts.

For the marinade, in a mixing bowl, add the yogurt, white wine, lemon juice, peeled crushed garlic cloves, smoked paprika, cayenne pepper, bay leaf and a little olive oil. Mix well. Cover and refrigerate 12 to 36 hours.

The next day or so, 30 minutes before cooking. Remove the chicken from fridge.

Peel and finely slice the brown onion. In a small saucepan on medium heat, add 1 tbsp olive oil, the sliced onion and thyme. Mix well and sweat onions. Turn heat to low, cover and give it a mix every 30 seconds or so. Once they start to caramelise, they can easily burn, so don’t walk away. Once the reach a soft jammy consistency, it’s ready.

Peel the avocado, place in a small bowl with a little salt and crush using a fork. You can also add a squeeze of lemon juice.

Heat up your BBQ or griddle pan reasonably hot, approx. medium-high. Oil the grate the place the chicken pieces on top. Flip over and brush on some of the remaining marinade. Chicken should be firm to touch once cooked. Remove and place under broiler or top shelf in BBQ. Place the cheese on top until melted.

Toast the brioche buns.

To assemble, spoon on the mayo first, then the avocado crush, the crispy lettuce, three thin overlapping slices of tomato. A little cracked pepper. Then place the hot chicken pieces. Two per burger. Then the reheated caramelised onion. Place the brioche bun on top and enjoy!