Smooth carrot puree can turn grainy, watery, or fibrous when the vegetables are undercooked or too much liquid is added.
This version uses one small potato for body and only enough cooking liquid to help the blender work.
Place the carrots, potato, water, and salt in a saucepan. Bring to a gentle boil, cover, and cook for 18 to 22 minutes. A knife should pass through the thickest carrot slice without resistance.
Drain the vegetables, reserving 150 ml of the cooking water. Let them sit in the warm empty pan for one minute so excess surface moisture can evaporate.
Transfer the vegetables to a high-sided jug or blender. Add the butter, olive oil, cumin, nutmeg, and lemon juice. Blend until smooth, stopping to scrape the sides as needed.
Add the reserved water one tablespoon at a time only if the blades struggle. This gradual approach prevents a loose, soup-like puree.
For an especially refined result, press the puree through a fine-mesh sieve. Taste and adjust the salt. If it is too thin, return it to low heat for 2 to 4 minutes, stirring constantly, until it thickens.
Serve hot beside roasted vegetables, chicken, or fish. Cool leftovers promptly, refrigerate in a covered container, and use within three days. Reheat gently with one tablespoon of water.
Fully tender carrots, controlled moisture, and patient blending produce a naturally silky carrot puree without needing cream.