Ingredients:

  • 50 g shallots, finely minced (about 2 medium)
  • 120 ml cold water
  • 1 tbsp (15 ml) apple cider vinegar
  • 45 ml fresh lemon juice (about 1 large lemon)
  • 226 g cold unsalted butter (2 sticks), cut into 1/2-inch cubes
  • 1 tsp (2 g) finely grated lemon zest
  • 1/4 tsp (1.5 g) fine sea salt, plus more to taste
  • 1/8 tsp (0.3 g) white pepper
  • 1 tbsp (15 ml) heavy cream

Instructions:

  1. Cut the cold butter into 1/2-inch cubes and refrigerate for 10 minutes.
  2. Mince the shallots until the pieces are about the size of lentils.
  3. Zest and juice the lemon. Keep the zest separate for the finish.
  4. Combine the shallots, water, apple cider vinegar and lemon juice in a 2- to 3-quart heavy-bottomed saucepan over medium heat.
  5. Simmer until about 2 tbsp (30 ml) of liquid remains, 5 to 7 minutes. The liquid should look glossy and syrupy, and the shallot pieces should cling to the bottom.
  6. Reduce the heat to low. The pan should be warm and steaming gently but not bubbling.
  7. Add the butter one cube at a time, whisking constantly. Wait until each cube is almost melted before adding the next, about 30 to 45 seconds per cube. Once the sauce thickens, add 2 or 3 cubes at a time. The sauce should turn pale gold and creamy.
  8. If the sauce starts to bubble or looks oily, lift the pan off the heat for a few seconds, whisk, then return it to low heat.
  9. When the last cube is nearly melted, remove the pan from the heat.
  10. Whisk in the lemon zest, 1/4 tsp salt, 1/8 tsp white pepper and the heavy cream.
  11. Taste the sauce and adjust with a few drops of lemon juice or a pinch of salt.
  12. For a smooth sauce without shallot bits, pour it through a fine-mesh strainer (optional).
  13. Transfer the sauce to a warmed bowl and serve right away.