Juicy Leftover Roast Beef and Onion Cheese Melt – Low Carb

I don’t know what to call this spontaneous lunch dish! But I will call it exquisite. I was looking for a way to add more fat to a leftover roast I made a few days ago and thus began one of my famous experiments.

The key to this recipe is the reduction of the beef broth while allowing the leftover roast beef and onions to simmer in the reducing liquid. I used the broth I reserved from an Instant Pot Roast.

Juicy Beef and Onion Cheese Melt = A great use of leftover roast
Simmering leftover roast with a sliced onion in homemade beef broth restores the beef back to its awesome juiciness.

Tip 1: You won’t oversalt a broth you are going to reduce if you go easy on the salt before the reduction process starts. Add more salt once it is reduced. As the liquid reduces, the saltiness will become pronounced.

I was amazed how good this tasted; it reminded me of French Onion Soup. This dish is low-carb and gluten-free and a breeze to prepare. It took 20 minutes from start to finish!

Tip 2: Invest in a kitchen food scale. I am a convert! My scale makes my life so much easier.

Leftover Roast and Onion Cheese Melt Recipe

Preheat oven to 400F


110g (4 oz) shredded leftover roast beef
I used leftover pot roast
34g (1 oz) onion, sliced very thin in matchsticks
1/3 cup beef broth – I saved the broth from the pot roast
1 tbsp coconut oil, avocado oil, or olive oil
50g (2.2 oz) total grated mozzarella/cheddar cheese mix – Swiss and cheddar would be a great mix as well.


Heat oil in a cast-iron pan, add onion, saute until translucent
Add leftover roast beef, stir fry for a minute.
Then add broth, allow the broth to reduce until just about all of it is evaporated.
This technique allows the beef to remain tender and juicy.
Salt and Pepper to taste after the sauce reduces or the broth will be too salty.
Transfer to a small greased ovenproof dish

Top with grated cheese.

Place the ovenproof dish in a 400F preheated oven for about 10 minutes or until the cheese is bubbly and melted.

Yields one substantial serving
Nutritional Values:
Calories 487
Protein 50g
Fat 30g
Net Carbs 4.7

©2017 Katherine Walden

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