Fuel8

Dinner

Smoked Mackerel with Warm Lentils and Watercress

Flaked smoked mackerel over lentils warmed with red onion and a mustard and cider vinegar dressing, with watercress on top. 30 g of protein for 471 kcal.

Calories
471kcal
Protein
30g
Fat
26g
Carbs
30g

Per serving, makes 1. 12 minutes of work. Published 8 September 2026.

Allergens

  • Fish
  • Mustard

Flags follow UK labelling rules and come from the ingredients as listed, not from any particular brand. Check the packet before cooking for somebody with an allergy.

Ingredients

  • Smoked mackerel80 g

    As sold. Most of the fat in any dish it is in.

  • Cooked lentils130 g

    Cooked weight, green or brown. A pouch is already this.

  • Watercress50 g
  • Wholegrain mustard2 tsp (12 g)
  • Red onion40 g
  • Olive oil4 g
  • Cider vinegarOne tablespoon

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Method

  1. Slice the onion finely and put it in a bowl with the vinegar and a pinch of salt for five minutes to soften and turn pink.

  2. Warm the lentils in a pan with a splash of water for three minutes.

  3. Whisk the mustard and oil into the onion and its vinegar, then toss the warm lentils through it.

  4. Pile the watercress on top, flake the mackerel over with the skin removed, and grind pepper over the lot.

Worth knowing

  • Ready-cooked lentils from a pouch make this a ten-minute dinner. Puy or green lentils; red ones go to mush when warmed.
  • Smoked mackerel is eaten cold here, which is how it comes. No cooking of the fish at all, and it is still 30 g of protein.

Other dinner recipes that share ingredients with this one, or every dinner between 450 and 600 calories a serving.

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Macros are calculated from the weights listed above using standard food composition values, and will shift with your own brands and measuring. Weigh what you can. This is a recipe, not dietary advice. The full health disclaimer is below.