Basic Vinaigrette

From The Minimalist Cooks at Home by Mark Bittman

Ingredients:
1/2 cup extra-virgin olive oil
3-4 tablespoons white wine vinegar (or Champagne Vinegar)
1 teaspoon Dijon mustard
salt and freshly ground black pepper to taste
1 large shallot, cut into chunks

Directions:
1. Place all ingredients except shallot in a blender. Blend until an emulsion forms. Taste for seasoning and vinegar. Add more vinegar if desired and blend again.
2. Add shallot and pulse until chopped. Serve immediately or may be refrigerated for 1 week. Bring to room temperature and whisk before serving.