Also, I frequently see recipes that
call for unsalted butter. Can salted butter be used or will this really
hurt the recipe?
Answer:When a recipe refers to "mirepoix" it is talking about a standard ratio of onions, carrots, and celery used in classical cooking. The ratio is 50% onion, 25% carrots, and 25% celery. Mirepoin is often used in the making of stocks and soups. Sometimes ham or bacon is added for more flavor. It is used to season sauces, stews, and soups. Mirepoix can also be used as a bed on which to braise meats.
Regular or Salted Butter vs. Unsalted Butter: If a recipe calls for unsalted butter and you only have regular butter, you can safely use the regular butter. In your recipe either omit the salt or use less.