To squeeze out the excess water from the potatoes, either press through a sieve or put grated potato into a clean tea towel and squeeze out the extra water.
We used 9cm diameter metal egg rings to cook the rosti but smaller rings can be used. Alternatively drop spoonfuls of the mixture into a heated and oiled pan. Lightly press mixture down with a fish slice or spatula. This will create a more free form rosti
To slow roast tomatoes. Pre-heat oven to 170°C (fan assisted). Cut tomatoes in half. Place cut side up on a baking tray lined with baking paper. Brush with olive oil and balsamic vinegar. Roast for 40-45 minutes.