Welcome Green Monsters! We're your online guide to making conscious choices that help people, animals and the planet.


Food Monster

Mashed Potato Casserole With Broccoli and a Cauliflower Gravy [Vegan]

This casserole has a layer of mashed potatoes, then a layer of cauliflower gravy, then a final layer of minced broccoli. The mashed potato layer has an undetectable can of white beans mixed in for protein. The gravy is made of puréed cauliflower as well as mushrooms. This ultimate comfort food of a casserole is creamy, dreamy, and a must-make for dinner.

Mashed Potato Casserole With Broccoli and a Cauliflower Gravy [Vegan]

This Recipe is :

High Carb VeganVegan


For the Mashed Potatoes:

  • 15 small russet potatoes (or 7-8 large ones)
  • 1 14-ounce can white beans
  • 2 tablespoons vegan butter
  • 1/2 cup non-dairy milk
  • 1 tablespoon salt

For the Gravy:

  • 6 ounces baby Bella mushrooms
  • 1 large head cauliflower
  • 1 cup non-dairy milk
  • 2 tablespoons nutritional yeast
  • 2 teaspoon salt
  • 1/2 teaspoon pepper
  • 2 cloves garlic, minced

For the Broccoli: 

  • 2 12-ounce bags of frozen broccoli
  • 1-2 teaspoon cajun seasoning


  1. Start by dicing your potatoes, with skin on, into even pieces. Place in large pot on stove and bring to a boil. Boil for 15 minutes.
  2. Once you place potatoes to boil, cut your cauliflower into chunks and place in a large saucepan, covered with water, to boil for 10 minutes.
  3. Slice mushrooms.
  4. Once cauliflower is done (check it by placing fork in it, should be very tender). Drain. Pour into high-powered blender along with 1 cup of non-dairy milk. Blend until completely smooth.
  5. Place blended cauliflower back on stove in the same saucepan on low-medium heat. Add mushrooms, 2 tablespoons nutritional yeast, 2 teaspoon salt, 1/2 teaspoon pepper, and the garlic into saucepan as well. Stir to combine. allow to cook for about 5 minutes to make the mushrooms slightly tender.
  6. While cauliflower gravy is cooking, drain your boiled potatoes. Leave them for a moment.
  7. Add your beans and 1/2 cup milk into high-powered blender and blend until smooth. Pour bean mixture into a large mixing bowl. Add drained potatoes, 2 tablespoons butter, and 1 tablespoon salt to large bowl as well.
  8. Beat potatoes with hand mixer (or by hand) until all potato ingredients are fully incorporated. Should be thick but creamy potatoes. Taste to see if need more salt, or add more milk if too thick.
  9. At this point, you should steam your broccoli, mine was able to be steamed in the bag, but you can do it however you please.
  10. Mash the potatoes into the bottom of a large casserole dish, smooth it as evenly as possible.
  11. Top with your cauliflower gravy mixture.
  12. Once broccoli is steam, and has cooled enough to touch, cut broccoli into very small pieces, almost minced. Sprinkle broccoli on top of the gravy layer. Add a bit of the cajun seasoning to the top of the broccoli.
  13. Place completed dish in oven for 25 minutes at 350°F.


BroccoliCauliflowerMushroomRusset Potato




Jennifer Harmon is the founder and recipe developer of the vegan food blog, Peppers and Peaches, which features all types of plant-based meals, snacks, and treats. Jenn’s goal is to spread the word that a plant-based diet is good for animals, the environment, and personal health.  Plus, it’s super tasty



Want to read more posts like this? Sign up for our newsletter below!​

Browse through recent recipes below:

4-Layer Blackberry Jam and Chocolate Crumble Bars [Vegan, Gluten-Free]

4-Layer Blackberry Jam and Chocolate Crumble Bars

Cauliflower Steaks With Pistachio Mint Pesto [Vegan]

Cauliflower Steaks With Pistachio Mint Pesto

Pan-Seared Lemon and Garlic Asparagus [Vegan]

Pan Seared Lemon and Garlic Asparagus 3

4-Ingredient Matcha Cashew Cups [Vegan]

Matcha Cashew Cups

Disclosure: One Green Planet accepts advertising, sponsorship, affiliate links and other forms of compensation, which may or may not influence the advertising content, topics or articles written on this site. Click here for more information.

56 comments on “Mashed Potato Casserole With Broccoli and a Cauliflower Gravy [Vegan]”

Click to add comment
Crystal McPherson
3 Months Ago

Donna Limley Michael Maury

Todd Glieden
3 Months Ago

Greg Rosas

Lynsanity Garaghty
3 Months Ago

Ivanna Maldonado Pyhmivongh Molly Pos

Lynsanity Garaghty
3 Months Ago

Ivanna Maldonado Pyhmivongh Molly Pos

Amy Ní Cholgáin
3 Months Ago

Seán Mc Veigh

The Vegan Chickpea
3 Months Ago


Janet Friedman-Fineman Nydick
3 Months Ago

Make sure there's plenty of Phazyme on hand or Beano.

Amanda Marie
3 Months Ago

Garth Hollar

Chiara Hutton
3 Months Ago

Grant Hutton looks delicious!

Sarah Harvey
3 Months Ago

Why the beans though? Just for protein or..? I like everything about this recipe except for that.

Hannah Lee
05 Feb 2016

It says just for the added protein

Sarah Harvey
05 Feb 2016

I just skimmed it, must have missed that. Thanks.

Subscribe to our Newsletter

Follow us on

Do Not Show This Again


Submit to OneGreenPlanet

Terms & Conditions ×