Mushroom Gravy Mashed Potato Casserole (Recipe)

Mushroom Gravy Mashed Potato Casserole (Recipe)

Mushroom Gravy Mashed Potato Casserole Recipe

This rib-sticking, deliciously hearty dish is perfect next to protein. Shown above, I paired it with almond crusted halibut. However, it can easily also do double duty, pleasing vegans very well on its own. If you are serving a vegan choose  olive oil instead of butter or ghee, and nut milk instead of milk. I make it both ways and it is just as good.

This casserole feeds eight or ten people, and no worries if you don’t eat it all, the leftovers are very welcome warmed up. Happy to have this on repeat, I have made it just for the two of us, so don’t think of it only for a feast, although it would certainly be great for that.

It takes a bit of time to do, although it is not difficult. Allow 2 hours, from just starting to when it is on the table. Keep on to the next step, while other things are cooking. Relax and enjoy the contemplative process.

3 cups kale, chopped
½ cup dry lentils, rinsed
1 ⅓ lbs yukon gold potatoes, peeled and chopped
3 garlic cloves, peeled and divided
3 tablespoons butter or ghee (or olive oil for vegan), divided
4 tablespoons milk (or nut milk for vegan), divided
sea salt and ground black pepper, to taste
1 small cooking onion, small dice
1 Tablespoon fresh rosemary leaves, minced
1 Tablespoon fresh sage, minced
1.5 lbs cremini mushrooms, chopped
2 tablespoons balsamic vinegar
1 teaspoon tamari, soy sauce, or coconut aminos
2 Tablespoons tomato paste
1 cup vegetable stock
1 Tablespoon arrowroot powder

Bring a medium saucepan of water to a boil. Add kale and simmer until it is just-wilted and bright green, about 1-2 minutes. Using a slotted spoon, remove the kale and place it in a small bowl. Run some cold water over it , then squeeze all the moisture out of it. Set aside.

Add the lentils to the boiling water. Cook until lentils are tender, about 20 minutes. Drain and set aside.

Preheat the oven to 375°F.

Wipe out the saucepan. Add the diced potatoes and one of the peeled garlic cloves to the saucepan. Cover the potatoes with cold water and place the saucepan back on the stove, over medium-high heat. Bring the potatoes to a boil and then simmer them until tender, about 18-20 minutes. Drain the potatoes.

Lightly grease a 9×13 (or 2 quart) baking dish with butter, ghee, or olive oil.

In a large bowl, combine the drained potatoes, 2 tablespoons of  butter or ghee (or olive oil), 2 tablespoons of the milk ( or nut milk), and plenty of salt & pepper. Mash the potatoes with a hand mixer or masher until the potatoes are smooth in texture. Roughly chop the squeezed, cooked kale, and stir it into the potatoes. Set aside.

Heat the remaining ghee (or olive oil) in a large, heavy pot over medium heat. Add the onions and sauté until translucent, about 3 minutes. Mince the remaining two garlic cloves and add them to the pot along with the herbs. Stir until garlic is fragrant, about 30 seconds.

Add the chopped mushrooms and stir. Place a tight-fitting lid on the pot and let it sit for 2 minutes. After two minutes, remove the lid and season the mushrooms with pepper. Stir. Place the lid on and let the pot sit for another two minutes.

The mushrooms should have reduced in volume by at least a third at this point. Add the cooked lentils to the pot. Stir the mushroom and lentil mixture and then add the balsamic vinegar, tamari (or soy sauce or coconut aminos), and tomato paste to the pot. Stir and scrape up any browned bits at the bottom of the pot. Season the mushrooms liberally with salt at this point.

Add the vegetable stock to the pot and stir. Bring the mushrooms to a boil.

In a small bowl, stir together the arrowroot powder and remaining 2 tablespoons of non-dairy milk to combine. Add the arrowroot slurry to the pot and stir. Let the mushrooms simmer until the surrounding liquid is slightly thickened, about 3 minutes.

Pour the mushrooms and gravy into the prepared glass baking dish. Dot the mashed potatoes on top, and then gently spread them over the entire surface of the mushrooms with a spatula.

Carefully transfer the casserole to the oven and bake until the mushrooms are bubbling and the potatoes are lightly browned, about 25 minutes. Remove from the oven and let it sit for a minute or two before serving.

Serve warm.


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I work to amplify good wherever I find it. I love color, texture, beauty, great ideas, nature, metaphor, deliciousness, genuine spirituality, and exploring new territory. I encourage authenticity, nurture creativity, champion sustainability, promote peace, and hope to foster a new renaissance where we all are free to be our most fulfilled, multifaceted, and terrific selves. Read more here.


  1. John gregory 2 years ago

    Hone…this is almost southern…looks divine!


  1. […] Mushroom Gravy Mashed Potato Casserole […]

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