Step 1

Melt butter in a small frying pan on low heat. Cook onion gently for 15 minutes until beginning to brown. Stir in sour cream, tomato and thyme.

Step 2

Preheat oven to hot, 200°C. Cut four 12cm rounds from pastry and arrange on a baking tray lined with baking paper.

Step 3

Prick each round with a fork and bake for 5 minutes. Remove from oven and spread evenly with onion mixture.

Step 4

Bake for a further 8-10 minutes until puffed and golden. Serve topped with a poached egg (see notes).