This Amazing Leftover Prime Rib Mongolian Beef Is A Family Favorite! (2024)

Flavorful prime rib Mongolian beef combines your tender pieces of prime rib leftovers with hearty, sweet, and savory Mongolian beef sauce for an amazing meal! Use leftover prime rib, roast beef, or steak to make this crowd-pleasing family dinner!

A sweet, savory, and completely satisfying prime rib leftovers meal!

This easy spin on the classic Chinese-American restaurant classic Mongolian beef is the perfect use of your leftover prime rib (or roast beef, or steak)! With such a quick prep time and equally fast cooking time, there's no reason not to whip up this tasty dinner!

Combine your perfectly medium-rare prime rib with a tasty sauce then serve over jasmine rice or my prime rib fried rice for an even more amazingly hearty meal!

🥘 Ingredients

• 1 lb Prime Rib (leftovers, thinly sliced, against the grain)
• ¼ cup Cornstarch
• 3 tablespoon Vegetable Oil (divided - 1 tablespoon and 2 tablespoon portions)
• 1 Tbsp Garlic (minced, chopped, or crushed)
• ½ Tbsp Ginger (fresh, minced)
• ⅓ cup Soy Sauce
• ⅓ cup Water
• ½ cup Dark Brown Sugar (dark brown sugar is recommended, but light brown sugar also works)
• 2 Green Onions (chopped or sliced on the diagonal in 1 inch lengths)
• 1 teaspoon Sesame Seeds (optional garnish)

🔪 Instructions

1. Slice and coat the prime rib. Slice your leftover prime rib portion against the grain into bite size strips, angling your knife at a 45 degree angle while slicing for wider cuts. Place the sliced meat into the cornstarch and coat evenly, let the coated beef strips sit for 10 minutes with the cornstarch on them.
2. Heat the first 1 tablespoon portion of the vegetable oil in a saucepan over medium low heat. Add the minced ginger and minced garlic for a quick 30 second cook, stirring frequently, and then add soy sauce, water, and dark brown sugar.
3. Increase heat to medium and bring the sauce to a boil until the sugar dissolves completely, about 2 minutes. Remove from heat and set aside (or transfer to a heat-safe measuring cup if using the same skillet as frying the beef in).While the meat is sitting in the cornstarch, heat up your wok or skillet at a medium heat. Add the second portion of 2 tablespoons vegetable oil to heat it up, making sure that it is hot, but that it doesn't start smoking.
4. Add the sliced beef, shaking excess cornstarch off if necessary. Cook for approximately 2 minutes, stirring to ensure even cooking, or long enough to get color on the edges of the strips. Using a slotted spoon, remove the beef to a wire cooling rack over paper towels. Drain or wipe out excess oil from your wok (or skillet) and return the wok to the heat.
5. Add the meat back to the wok and cook for one minute (still on medium heat). Add the sauce and cook, stirring frequently, for an additional 1-2 minutes until thickened.
6. Remove from heat when done and serve immediately. Garnish with chopped green onion and/or sesame seeds if desired.

😋 More Prime Rib Leftovers

• Prime Rib Beef and Barley
• Prime Rib Stuffed Mushrooms
• Taquitos
• Chili
• Prime Rib Stroganoff

📖 Recipe Card

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