Start by peeling the celeriac carefully using a sharp knife. The skin is thick and rough, so take your time. Cut it into small cubes so it cooks evenly and blends smoothly later.

Place the chopped celeriac into a large saucepan. Add the garlic clove and enough water to cover everything. Bring it to a boil, then reduce heat and simmer gently until the pieces become very soft.

After about 20 minutes, check the celeriac with a fork. It should feel tender and break easily. If it still feels firm, cook it a little longer. Soft texture is key for a smooth puree.

Carefully drain all the water from the saucepan. Let the celeriac sit for a minute to release extra moisture. Removing water helps keep the puree thick and creamy instead of watery.

Transfer the cooked celeriac and garlic into a blender or food processor. Blend until you get a smooth mixture. You can also use a hand blender if that feels easier in your kitchen.

Now add the butter and double cream into the mixture. Blend again until everything becomes silky and rich. This step gives the puree its creamy and luxurious texture.

Add salt, black pepper, and a pinch of nutmeg if you like. Mix well and taste the puree. Adjust seasoning slowly until you are happy with the flavor.

Serve the puree warm for the best experience. It should feel smooth, soft and slightly fluffy. Enjoy it as a side dish with your favorite main course.