Lemon butter

Soften butter until spreadable, then beat in finely grated lemon zest and a little lemon juice, adding the juice gradually so the butter does not split. Chill it in a small log, then slice it over hot fish, asparagus or new potatoes.

Yes: melt it gently and spoon it over cooked fish, prawns or vegetables, or use it to finish a pan sauce. Avoid frying with it over high heat, as the milk solids can brown before the lemon flavour has a chance to infuse.

Keep it covered in the fridge and use it within a few days, especially if it contains fresh lemon juice. For longer storage, freeze it in a log or small portions and thaw what you need in the fridge.

It works particularly well with grilled salmon, white fish, prawns, asparagus and steamed green beans. A slice melting over hot new potatoes or corn on the cob is an easy way to use it, too.

No: lemon curd is sweet, soft and made with eggs, so it suits toast, tarts and desserts rather than savoury food. Lemon butter is rich and buttery, with a fresh citrus flavour that complements fish and vegetables.

No. Lemon butter is usually softened or melted butter flavoured with lemon zest or juice; beurre blanc is a French sauce made by whisking cold butter into a reduced mixture of wine or vinegar and shallots.

It can add a gentle citrus flavour to biscuits, cakes and pastry, but it is not a direct replacement for plain butter if it contains lemon juice, which adds moisture and acidity. For a predictable result, use plain butter and add finely grated lemon zest to the recipe.

Lemon butter is rich because butter is its main ingredient: 667 kcal per 100 g. A thin scrape on bread or a small slice melted over fish uses much less than a thick spread.