1 kg potatoes, peeled
salt and freshly ground black pepper
2 tblsp olive oil
225 g onions, peeled and thinly sliced
3 cloves garlic, crushed
4 large tomatoes, thinly sliced
2 tblsp freshly chopped tarragon or 1 tblsp dried tarragon
200 g mature cheddar cheese, grated

Parboil the potatoes in salted water. Drain, allow to cool slightly, and slice.

Pre-heat the oven to moderately hot.

Heat the olive oil in a saucepan and gently sauté the onion and garlic for 5 minutes.

Grease a large ovenproof dish. Place half the potatoes in a layer at the bottom of the dish. Top with a layer of half the onions, half the tarragon, 2 sliced tomatoes and half the grated cheese. Season well, and repeat with the remaining ingredients to create a second layer. An extra layer of cheese may be added on top if desired.

Cook uncovered in the oven for approximately 45 minutes, or until the cheese is well melted into the other ingredients and browned on top.