Begin with making your dough. Mix the flour with the baking powder and salt in a bowl with half a tbsp of oil, a little water and the olives. Knead into a soft dough, then put it in a clean bowl, cover and leave to rest.
To make the avocado filling, dice the tomatoes and mix with the garlic, thyme and a splash of oil. Season with a little salt, pepper and lime juice. Set aside for later.
Pre-heat the BBQ over a medium heat for 2-3 minutes with the Plancha Grill Top in place. Divide the dough into several small balls then a little oil to the flat side of the Plancha along with the dough balls. Once the bottom is slightly baked, flip them over and squash down a with a spoon or spatula. Cook for a couple of minutes on each side until golden.
Cut the avocados in half and remove the stone. Season the cut side with a little salt and oil. Add the avocados to the ribbed side on the Plancha cut side down, and cook for 3-4 minutes. Remove from the BBQ and stuff with the tomato filling, serve immediately with the olive bread on the side.