Gratin of crushed potato - and 'towers' more on top

This is one of those recipes.... you will give it a glance and think, too complicated and move on. STOP. HALT. REVERSE. At least read it and you will realise its not that complicated, looks impressive and yep, as usual, it tastes good! Ha, like I am going to post a recipe and tell you it tastes awful?
It is easy to prepare in advance and bake just before eating. Serves 4 adults very comfortably. Err on the generous side with potatoes and be stingy with the other ingredients. I bought those open metal rings from Boardmans, they are about 7 cm high. Otherwise just bake in tea cups, turn out and turn over again. Yikes.
Gratin of crushed potato, aubergine and spinach with thyme cream

400g aubergine
olive oil
1 medium onion,finely chopped
2 garlic cloves, crushed
1 small chilli, chopped
1 tsp cumin seeds ground (or powder)
1tsp coriander seeds, ground (or powder)
leaves from 4 sprigs fresh thyme
4 ripe tomatoes, peel and chop (or 1 tin tomatoes, drained)
100ml red wine
2tsp tomato puree
600g potatoes
1T chopped chives
salt and pepper
200g spinach, cooked and chopped
50g goats cheese, sliced into 4

Thyme and caper cream:
100ml vegetable stock
100ml white wine
200ml cream
2tsp tiny capers
1tsp fresh thyme leaves

Whew!!!! Preheat oven to 180C. Chop aubergine into smallish cubes, toss in oil and roast about 15 minutes till cooked through.
Fry onions 2-3 minutes, add spices, garlic, chillies and thyme. Cook 5 minutes, add tomatoes and red wine and cook slowly till thick and well reduced, stir aubergines in and season lightly.
Peel and boil potatoes, then chop coarsley and fry in 2T olive oil, stirring and breaking so you have a chunky, well fried half mash. Add chives and season
Cover a baking tray with baking paper, put rings on top, line with a strip of baking paper. I don't bother to grease the tins. Press in a layer of potato (divide between 4 rings), top with spinach then tomato mix, top with slice of cheese. Bake for 15 minutes.
Reduce stock and wine to half by boiling rapidly, add cream and reduce again, add capers and thyme and little seasoning.
Remove gratins from oven, plate and slide rings off. Dress with thyme cream and wait for your guests to be impressed. Serve with some veg and salad leaves. Hmmmmmmm