Mini onion parmesan tatin tarts

INGREDIENTS

For the crust: For the filling: DIRECTIONS
 * 170g flour
 * 70g soft butter
 * dash of salt
 * 2 tablespoons of water
 * 3 shallots
 * 3 small onions
 * 1 tablespoon brown sugar, not fine
 * 40g butter
 * 100g parmigiano reggiano
 * salt, pepper
 * Knead all ingredients for the crust together (add water last), until you get a ball. Wrap in cling film and chill for 30min.
 * Peel the shallots and onions and cut them into half circles.
 * Melt butter in a pan. Add shallots and onion, sprinkle with brown sugar and let caramelize for 15 min at very low heat. Add salt, pepper and mix together with the cheese.
 * Preheat oven at 180°.
 * Flatten dough and cut out top-of-muffin-tin-shaped circles. Spread onion mix at the bottom of the muffin tins and cover with circles of dough.
 * Bake for 35 minutes.