Roast Beef with Creamy Hot Mustard Sauce

Roast Beef with a beautifully creamy mustard dressing: it looks like your Sundays are sorted! I love my chef’s knife (and sharpen my baby daily), BUT in cases like this, I dig out my electric carving knife. I am not entirely sure why: maybe because it makes me feel like I am living in the 80’s but it is a little more accurate and will ensure that everyone gets a decent, even-sized slice (or two or three) of the good stuff… Check out the Side Dish ideas to serve alongside.

– – – – – – PER SERVING – – – – – –
Carbs 4.3g | Fat 26g | Protein 43g
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Exciting news for foodies: Monya’s cookbook KETO KITCHEN (published by Kyle Books, London 2020) is coming to the market this summer. Its currently available to pre-order on Amazon.

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Roast Beef with Creamy Mustard Sauce

Moist and delicious roast beef with a beautiful creamy mustard dressing - your Sundays are sorted! (For my UK readers, scroll to the end of the recipe to see image ads of the products I use.)
Course Main Dish
Cuisine General
Prep Time 5 minutes
Cook Time 1 hour 55 minutes
Total Time 2 hours
Servings 6


  • 1.3 kg (2.9 lb) beef roasting joint
  • salt and freshly ground black pepper
  • 150 g (5.3 oz) double cream
  • 30 g (1.1 oz) sour cream
  • 50 g (1.8 oz) hot English mustard


  • Preheat the oven to 170°C (fan oven). This is 190°C for conventional ovens (or 375°F / gas mark 5).
  • Season the beef on all sides with salt and freshly ground black pepper. Place into a small, deep roasting tray and wrap the entire tray very well with foil, ensuring its air-tight.
  • Place in the oven for 90 minutes. (NOTE: If your joint is smaller or larger than mine, simply follow the basic rule: cook for 6 minutes for every 100g / 3.5oz of the beef's weight indicated on the packaging).
  • When done, remove the beef from the tray and set aside on a tray and wrap again in a clean sheet of foil and set aside to rest.
  • Tip all the juices from the tray (there will likely be a lot) into a pan and reduce by half over a high heat.
  • Once reduced, add the cream, sour cream and mustard. Whisk well to combine and reduce to low heat, allowing the sauce to simmer gently and reduce further. If it curdles or looks like it is 'splitting', use a hand blender to bring it together.
  • Keep your eye on the sauce, as it can boil over while you are sipping your Sunday tipple and not paying attention...
  • Allow the sauce to reduce to a thick consistency. It should coat the back of a spoon. Set aside to keep warm.
  • At this time, the beef would have rested for at least 15-20 min (perfect). To serve, snip away any string or twine (if you bought it like that) and slice it thinly (or thickly: no rules!) using a good quality knife. (I have an amazing chef knife which I sharpen daily, but for roasts like this, I always use my electric carving knife).
  • Serve with the deliciously rich sauce and your favourite vegetables (search SIDE DISHES on the site for fantastic keto veg ideas, many include keto Yorkshire puddings and other great options!)


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Calories: 425kcal | Carbohydrates: 4.3g | Protein: 43g | Fat: 26g

Roast Beef with Creamy Hot Mustard Sauce
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Roast Beef with Creamy Mustard Sauce
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Average Rating
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Nutritional Information per serving
Calories                         425Kcal / 1778kJ
Fat                                 26g
Carbohydrates               4.3g
Protein                           43g

Eggs (may be found in some brands of sour cream)
Wheat (check the labels of your roasting joint)

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Disclaimer: The nutritional analysis, macro and allergen breakdown of the recipes on this site are meticulously calculated using the cloud-based software NUTRITICS®. NUTRITICS® is fully approved by the relevant Trading Standards organizations and is EU and FDA-compliant. The author, Monya Kilian Palmer is trained in using this superior software in order to provide you accurate data. The author is not a medical professional and this website has been designed only to provide you with recipes to suit the keto lifestyle you have chosen and discussed with your GP. The macros calculations are provided as a courtesy to you based on Monya’s weighing of ingredients when creating the dishes. If Erythritol (a sugar polyol) has been used in any of the recipes, it has already been manually excluded from the final carbohydrate count for you.

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