# Nigel Slater’s kitchen diary: roast onions and spinach polenta

2025-10-23

**Ingredients**

- 3 medium onions
- 50ml olive oil
- 50g butter
- 10 sprigs thyme
- 500ml water
- 500ml milk
- 3 bay leaves
- 150g fine polenta
- 400g spinach
- 50g butter (for polenta)
- 50g parmesan
- 150g mature cheddar

**Method**

1. Preheat the oven to 200°C/gas mark 6.
2. Peel and cut the onions in half, then into quarters. Place them in
a roasting tin, pour over olive oil, and dot with butter. Scatter
thyme sprigs among them. Roast for 40-45 minutes until soft and
translucent, basting once or twice. 
3. For the polenta, bring water and milk to the boil in a large,
heavy-based pan with bay leaves. Salt the water generously, then pour
in polenta, stirring continuously. Lower the heat and keep stirring
regularly until the polenta is cooked and behaves.
4. Steam spinach in a pan with a lid for a few minutes, then squeeze
out water with your hands.
5. Cut butter into small pieces and add it to the polenta, then stir
in the spinach and finely grated parmesan. Grate cheddar cheese and
stir it in as well.
Check the seasoning.
6. Spoon the polenta onto a serving dish and place the roast onions on top,
pouring any butter from the roasting tin over them.