* Ideally, you should make the sauce in the pan you've used to cook the onions, but if you have a stash of pre-cooked onions on hand, just follow the directions in the note below to finish the sauce.
Yield: 2 servings
- 1 medium russet potato** (8 to 9 ounces)
- 1 tablespoon butter (or to taste)
- 1/4 cup cream or half-and-half (or to taste)
- 2 tablespoons sour cream
- 1/4 teaspoon kosher salt
- 1/8 teaspoon fresh ground black pepper
- 1/3 cup slow-browned onions, divided
- 1/4 cup dry sherry
- 1/4 teaspoon dried thyme
- 1/2 cup low-sodium beef broth
- 1/8 teaspoon Dijon mustard
- 1/8 teaspoon brown sugar (optional)
2. Pour into a colander or strainer to drain.
3. Press through a ricer or food mill (or mash by hand). Add butter, cream, sour cream, salt and pepper and stir to combine. Add more cream if necessary to make a smooth puree. Gently stir in about two tablespoons of the browned onions and adjust seasoning if necessary. Keep warm until ready to serve.
4. For the onion sauce, remove all but about 1/4 cup of the onions from the pan you've cooked them in, and reserve for another use. Heat the pan for a minute or so on medium high heat and pour the sherry and thyme into the pan. Bring to a boil, scraping up the browned bits from the bottom of the pan. Reduce the sherry by about half and then add the beef broth. Continue boiling until sauce is reduced by about half and has the consistency of a thin syrup. Stir in mustard and taste. If the sauce seems too acidic, add the optional brown sugar.
Note: If you're using onions that you've cooked previously, bring the sherry and thyme to boil in a small sauce pan and reduce by half. Add about 1/4 cup of cooked onions and the broth and continue with the recipe.
**While I think russets (also called Idaho or baking potatoes) are best for mashing because of their low moisture content and "floury" interior, you can also use Yukon golds.