To make homemade champagne vinegar, store leftover champagne in an open, widemouthed jar at room temperature. In a few weeks, it will be vinegar.
- 2 teaspoons Dijon mustard
- 1/4 cup champagne vinegar
- 3/4 cup extra-virgin olive oil
- 1/2 teaspoon salt
- Pinch of freshly ground black pepper
In a small bowl, combine mustard and vinegar; whisk together. While whisking constantly, slowly drizzle in olive oil. Season with salt and pepper.