Dice the celeriac into 1/2 inch cubes, taking great care not to cut yourself (to make cutting the celeriac easier, first slice off one end so that it is flat and stays steady on the board).
Put a heavy based, large frying pan or casserole dish on a high heat, and 3 lugs olive oil, then add the garlic, celeriac and thyme, plus a quick grind of salt and pepper.
Stir briskly around the pan for 5 minutes until lightly coloured.
Turn down the heat, add the stock, and simmer for 25 minutes.
Remove from the heat and serve either in whole cubes, fully mashed, or just mash some of the cubes which will give the dish an amazing flavour and texture.
1 celeriac, peeled
Extra virgin olive oil
1 handful thyme
2 cloves garlic, crushed
4 tbsp veg stock
Sea salt and black pepper