Heat olive oil in a
non-stick pan, add onions and saute till golden brown. Add garlic, thyme, brown sugar, salt and 1 tbsp white wine vinegar and cook till onions are caramelized.
Take cherry tomatoes,
add salt, pepper powder and 1 tbsp white wine vinegar in a bowl and toss.
Arrange the tartlet
shells in a serving plate, put a spoon full of the onion mixture in each shell.
Top with cherry
tomatoes mixture on one side. Keep 1 mozzarella cheese cube and 1 parsley sprig over the onions in each shell and serve.