First make the dough. Mix the flour with half a teaspoon of baking soda and half a teaspoon of salt and put it in a bowl with half a tablespoon of olive oil, water and olives. Knead into a soft, slightly sticky mass. Set the dough aside and let it rest for a few minutes.
For the avocado filling, dice the tomatoes, chop the garlic and thyme and mix with a dash of olive oil. Season with a little salt, pepper and lime juice. Cut the avocados in half and remove the core. Sprinkle the cut sides with a little olive oil and a pinch of salt.
Preheat the braai and brush the smooth side of the baking sheet with olive oil after 1 to 2 minutes. Divide the dough into several small balls and place them on the plate. Once the bottom is lightly baked, turn the dough balls and press them a little flat.
Place the avocados on the rack with the open side down. Turn the dough after about 1 to 2 minutes to bake it crispy on the other side. Remove the avocados and the olive bread from the braai after another 2 minutes. Fill the avocados with the tomato-thyme filling and serve with the bread.