Preheat oven to 200°C/180°C (fan forced).
Combine garlic and olive oil in small bowl. Season with salt and pepper. Brush bread with oil mixture on both sides and place onto a lined baking tray. Place in the oven and bake for 15 minutes. Remove from oven, allow to cool and break into pieces.
Place all dressing ingredients in a medium bowl. Whisk for 5 minutes or until well blended.
Place lettuce into a large mixing bowl. Add dressing and toss to combine. Transfer lettuce to serving platter and top with parmesan, croutons and avocado slices.