I use this fresh-tasting sabayon to coat my mollet egg & courgette tarts. It’s also good with cauliflower or broccoli, or tossed with spaghetti and sprinkled with Parmesan.
100g (3½oz) baby spinach leaves
50g (1¾oz) watercress leaves
salt and freshly ground pepper
2 egg yolks
40g (3 tbsp) butter, diced
Wash the spinach and watercress leaves, then drain well. Bring 100 ml (scant ½ cup) lightly salted water to the boil in a saucepan. Immediately drop in the spinach and watercress leaves, cook for 1 minute, then tip the mixture into a blender and whiz for 1 minute. Pass the purée through a chinois into a small bowl, then set over ice to cool the mixture quickly.
Two-thirds fill a saucepan (large enough to hold a round-bottomed bowl) with warm water, and heat gently. Pour the spinach and watercress purée into the bowl and set over the pan. Add the egg yolks, whisking as you go.
Whisk the mixture constantly for 8 – 10 minutes (see Classic sabayon), until it has a light ribbon consistency. When the sabayon reaches 70ºC/158ºF, it is ready.
Remove the bowl from the saucepan, then gradually whisk in the diced butter. The sabayon should have a rich, shiny texture. Season with salt and pepper to taste and serve immediately.
If preferred, use 1 tbsp English mustard powder dissolved in a few drops of warm water in place of the Dijon mustard.