I love having vinaigrettes ready in the fridge, but really hate the flavour of prepared grocery store stuff, so I'm always on the lookout for good ones that can last for a couple of weeks without separating or going off.
I first had this vinaigrette at Bouchon, Thomas Keller's Napa Valley bistro (aka: the place you get referred to when you CAN'T get into his ridiculously overbooked neighbouring restaurant, French Laundry). Bouchon is beautiful, lively, and the food is so simple and so perfect that I sprung for the $70 cookbook. It's worth it for the pictures alone.
Not only is this recipe incredibly simple, it works each and every time and can last weeks in the fridge. Just mix up a batch (10 minutes max) and store it in a squeeze bottle on the fridge door. Whip it out when you need to toss a quick salad, or brighten up warm veg like new potatoes, green beans, asparagus off the BBQ...pretty much anything. This is also the recipe I use when I make Nicoise Salad.
BOUCHON HOUSE VINAIGRETTE (recipe as it appears in "Bouchon", by Thomas Keller with Jeffrey Cerciello. Artisan NYC, 2004.)
1/4 cup Dijon mustard
1/2 cup red wine vinegar
1 1/2 cups canola oil
Combine the mustard and vinegar in a blender and blend at medium speed for about 15 seconds. With the machine running, slowly drizzle in 1/2 cup of the oil. Don't be tempted to add all the oil to the blender or the vinaigrette will become too thick. It should be very creamy. Transfer the vinaigrette to a small bowl and , whisking constantly, slowly stream in the remaining 1 cup of oil. Makes 2 1/2 cups.