In a medium saucepan, add a splash of olive oil or a little butter over medium heat. Once the pan is hot, add the finely chopped shallots. Sauté for about 2-3 minutes until they become soft and translucent. You’re looking for them to release their natural sweetness, not brown.

Pour in your white wine and white wine vinegar (if using). Stir the mixture to release any flavorful bits stuck to the pan. Let this cook for 5-7 minutes, allowing the liquid to reduce by about half. This step intensifies the flavors, so don’t rush it!

If you're opting for a richer, creamier sauce, add heavy cream now. Stir it into the reduction and bring it to a gentle simmer for 2-3 minutes. This will give your sauce that indulgent texture and smooth finish. If you prefer a lighter sauce, you can skip this step.

Now comes the fun part—creating that velvety texture! Slowly add the cold, cubed butter, one piece at a time, whisking constantly. As each cube melts, the sauce will begin to thicken and become creamy. Keep whisking until all the butter is incorporated and the sauce is smooth and glossy.

Stir in fresh lemon juice and lemon zest. The citrusy acidity will brighten the sauce and cut through the richness, making each bite balanced and refreshing. Taste and adjust with salt and freshly ground black pepper.

If you’d like, finish the sauce with a handful of fresh herbs like tarragon or chives for a burst of freshness. These herbs add a subtle flavor that complements the lemony notes beautifully.