Avocado cream with tomato and olive oil

Ingredients (for two):
For avocado cream:
1 avocado
150 mL cold vegetable broth
juice of 1/2 lemon Tbsp yoghurt
salt, pepper
For tomato:
1 tomato
For frozen olive oil: 3 tbsp olive oil
1 tbsp lemon juice
For garnish:
parsley

Preparation:
Combine avocado, broth, lemon juice, salt, pepper in food processor. Process. Refrigerate until use. Skin and seed tomato. Cut into small cubes. Whisk olive oil and lemon juice. Put in ice cube tray and freeze. Just before serving, heap half of the tomatoes in each of two deep dishes, pour avocado cream so that they surround the tomatoes. Take one cube of frozen vinaigrette, chop, and place on top. Garnish with parsley.