Herb sauces are great stuff: they let the flavor of an herb come through proud and clear while lightly cloaking food. But they are prone to breaking—let an herb purée sit for five minutes and the solids will clump together and leave an ugly pool of green water on the plate. A small pinch of xanthan gum will hold the sauce together and provide a velvety texture to what may otherwise be too thin.
Xanthan gum is one of the most common and easy to use modernist ingredients. You can use it to thicken just about any liquid, and a little goes a long way. (Conversely, too much will turn your sauce into spackle.) It is relatively easy to find as these ingredients go, especially as it's also used in gluten-free baking, but you can also buy it at L'Epicerie.
Use this coulis as a light sauce on roasted potatoes, pan-seared chicken breasts, or as a salsa on tacos.
Cilantro Coulis Recipe
- 1 bunch cilantro, washed, thick stems removed
- 4 cups boiling water
- Lime juice, to taste
- Aleppo chile, to taste
- Salt, to taste
- Sugar, to taste
- Xanthan gum, 0.25% of total blended ingredients above
Weigh blender on scale and note weight in grams.
Blanch cilantro in boiling water for 30 seconds, then rinse in cold water until cool. Add to blender with just enough water to blend to a smooth purée, then add small amounts of lime juice, aleppo, salt, and sugar to taste and blend till smooth.
Transfer blender and purée to scale and subtract weight of blender from total weight. Multiply weight of liquid by 0.0025 and measure out that amount of xanthan gum. Add to blender and blend till smooth. Pour through a fine mesh strainer and serve as a finishing sauce or garnish.
blender, scale accurate to 0.1 gram