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Mustard Roasted Fish
with lentils, peas, and spinach

Active: 20 minTotal: 35 min

This fish dish is an absolute crowd pleaser and also super simple to make. Make it extra indulgent with a few more scoops of dairy.


Lentils, Peas, & Spinach:
  • French / Green lentils, dried - 1 cup
  • Garlic - 4 cloves, minced
  • Onions - 1, diced
  • Cooking oil - 1 Tbsp
  • Chicken broth / stock - 2 to 4 cups
  • Frozen peas - 4 oz
  • Dried thyme - 1 tsp
  • Baby spinach - 4 oz
Mustard Roasted Fish:
  • Shallots - 2 Tbsp, minced
  • Tilapia or cod (4 to 6 oz fillets) - 4 fillets
  • Dried thyme - 1/2 tsp
  • Lemons - 1, juice & wedges
  • Capers (opt) - 1 Tbsp
  • Dijon mustard - 1 Tbsp
  • Creme fraiche - 1/4 cup

Nutrition Facts

Serving Size: 1 serving
Servings Per Recipe 4
Amount Per Serving
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% Daily Value
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  1. Lentils – Give them a quick rinse, and soak in 3x the amount of water the night before or morning of cooking
  2. Garlic / Onions / Shallots - Prep as directed
  3. Fish - Rinse and dry with paper towels


  1. Preheat oven to 425F (218C) degrees
  2. Heat a >3.5 quart (3.3 liters) Dutch oven over medium-high heat. Add 1 tbs. (15 ml) cooking oil and then minced garlic to heated oil. Add diced onions with a dash of salt. Sauté for 3 minutes, until softened and translucent
  3. Add drained lentils and then add 2 cups (472 ml) of stock / broth if you soaked them overnight or 3 cups (705 ml) of stock if not soaked. Add 1 tsp. (5 ml) thyme and 1⁄2 tsp. (2.5 ml) kosher salt. Cover and bring to a boil. Simmer uncovered for 10 minutes if lentils were soaked, 25 to 30 minutes if not soaked
  4. Mix together 1⁄2 tsp. (2.5 ml) dried thyme, shallots, 1 tbs. (15 ml)lemon juice, capers, Dijon mustard, and crème fraiche with 1⁄4 tsp. (1.25 ml) kosher salt
  5. Place fish into a baking pan. Sprinkle with salt and pepper and then cover with mustard mixture. Bake in oven for 12 to 15 minutes depending on thickness of fish
  6. Check if lentils have absorbed all their liquid. Add peas and spinach. Cook for another 2 to 3 minutes and then season to taste with salt and pepper
  7. Enjoy fish with lemon wedges. The mustard / crème fraiche turns into a natural sauce. Serve over lentils

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This meal has 69 reviews

We liked the mustard sauce. I didn't have creme fraiche so I subbed sour cream. I liked the lentils - a nice change from rice - hubs ate them because they were healthy.

By: Nancy
Posted: Nov 27, 2018
Diet: Original

Very good. Definitely restaurant quality. We completely followed the recipe, using cod, except we used Fage plain yogurt instead of creme fraiche. The directions are a little out of order, and it took longer than the specified time for the soaked lentils to absorb the soup. OMGOSH. It was wonderful.

By: Susan
Posted: May 13, 2017
Diet: Original

Re-heated with sesame oil! Super tastyyyy

By: Zivi
Posted: May 09, 2016
Diet: Original

Will add this to my go-to recipes

By: Charmaine
Posted: Jul 04, 2015
Diet: Original

This was a major hit for us. Both my 3.5 year old and 1 year old devoured everything. The sauce was a great compliment to the fish, didn't overpower the flavor.

By: Brandi
Posted: May 14, 2015
Diet: Original

I didn't care for the lentils the first time I made this, so I always substitute something else, but the mustard on the fish is amazing.

By: Jennifer
Posted: Apr 26, 2015
Diet: Original