I like my dressing to be tangy, as I find it balances out once it is added to a salad. If you find it a bit too strong, add some more sour cream, or decrease the quantity of vinegar and mustard. This dressing will keep for a few days in the fridge, although it will thicken slightly due to the olive oil. Just give it a stir before using. Note that I have used a 20ml Tablespoon for this recipe.