Place olive oil and garlic in a frying pan. Fry (stirring occasionally) over a medium heat until the garlic is golden brown; approximately 2 minutes. Add eggplant and zucchini to the frypan, fry until the eggplant is brown and tender; approximately 5 to 7 minutes.
Add the tomato chunks to the frypan, stir the mixture until the tomato becomes a pulp. Mix in salt, oregano and basil. Stir the entire mixture over the heat for 2 minutes, remove frying pan from heat then let the mixture cool.
Preheat oven to 170 degrees C.
Slice the bread into 12 (3cm) slices. Distribute garlic powder and butter evenly over the top of each slice. Place the slices directly onto the oven rack (do not use a baking tray, the bread will get crisper this way). Let the bread heat for 3 to 5 minutes.
Remove the bread from the oven and arrange them on a serving platter. Spread the vegetable mixture over the 12 bread slices, distribute the topping as evenly as you can. Serve immediately.