Heat a frying pan and toast the pine nuts on a medium heat for about 3 mins. until golden brown. Cool them on a plate.
Roughly slice the garlic. Place in the blender, bowl of the hand blender or food processor. Add the cooled pine nuts and cheese. Blend briefly so the mixture is still coarse. Add the basil and blend briefly. Add the olive oil. Blend until you have the desired texture: a smooth or coarse pesto. Add extra olive oil if the pesto is too thick to your taste. Season with salt and pepper.
Divide the salad leaves over four plates. Halve the cherry tomatoes. Arrange the tomato halves and the drained mozzarella over the salad.
Slice the avocado all the way around the stone. Twist the two halves apart. Remove the stone, scoop the flesh out of the skin and cut into thin slices. Arrange the slices over the salad and drizzle with the pesto.
