Vegan Mushroom and Onion Scalloped Potatoes! Prepare for a flavor explosion that will have you saying, “These Scalloped Potatoes are a spud-tastic sensation!”

Rich, velvety, and bursting with the savory goodness of onions and mushrooms, this Vegan Mushroom and Onion Scalloped Potatoes is a true crowd-pleaser that will elevate any dinner. Each creamy bite is a symphony of flavors that will have your taste buds singing with delight.

Whole Food Plant Based, Vegan, plant based, oil free, refined sugar free, no highly processed ingredients and gluten free.

Hi there, Ameera here!

Discover the recipe that made my dad go bananas! He couldn’t get enough of the savory onions and mushrooms nestled between layers of creamy scalloped potatoes. Trust me, this dish is a winner that will have you coming back for seconds.

The mushrooms tend to color the sauce, which creates pools of darkened sauce, but don’t let the look of this humble dish deter you from giving it a try. It may not be the prettiest of scalloped potatoes, but it makes up for its appearance in yummy goodness.

If you love mushrooms and potatoes, you gotta give this one a try!

Tips for Success:

• Flavor Profile: This Vegan Mushroom and Onion Scalloped Potatoes dish are perfect comfort food. Deliciously rich, velvety, and full of onion and mushroom goodness, they are sure to please.
• Onions: We used 2 medium yellow onions or 4 small yellow onions. We quartered them, then sliced them thinly. The onion flavor is prominent. If you are not a huge onion fan, then consider skipping this recipe.
• Mushrooms: We used Baby Bella mushrooms; you can use your favorite mushrooms in this dish.
• Potatoes: We used Russet potatoes for this dish. Feel free to use your favorite potato in this recipe.
• Slicing the Potatoes: Slice the potatoes thinly to ensure they become tender within a reasonable amount of time.  We used 1/4-inch slices.  If you slice the potatoes too thick, then it will take longer to cook the potatoes until tender.  If you slice them too thin, then they will fall apart while par-boiling them.
• Par-Boiling the Potatoes: Start the count of 5 minutes as soon as the potatoes come to a boil. After 5 minutes of gently boiling, then immediately drain them and gently run some cold water over them for 10 seconds. They should still be firm and not tender.  This process does several things, it cuts down on the time in the oven, it seasons the potatoes with sea salt, and it sets the starches in the potatoes.  Do not overcook, the dish will be too mushy. It is better for them to be undercooked than overcooked during the par-boil process.
• Amount of Sliced Potatoes: Do not use more than 1 ½ pounds (24 oz.) of potatoes to avoid a dry dish. The measurement of potatoes if after they have been peeled and sliced.
• How to Test for Potato Tenderness after Baking in the Oven: Take a sharp knife and pierce several potatoes. If the knife slides in easily, then the potatoes are tender.
• Sequence of Layering:
  • ¾ cup of sauce
  • Half of the par-boiled potatoes (evenly distributed in a single layer)
  • ½ cup Sauce
  • All the sautéed onions, mushrooms, and spinach (evenly spread out)
  • ½ cup Sauce
  • Other half of the par-boiled potatoes (evenly distributed in a single layer)
  • Remaining Sauce
• Dividing the Sauce for the Layering: There are 4 layers of sauce. You want approximately ½ cup of sauce on layers 2 and 3 with the remaining (most) on the top layer.  The key is to have the top layer of potatoes completely coated in sauce. If you note while layering that you may have used too much sauce in the 1^st and 2^nd sauce layer, skip the 3^rd layer of sauce and place all of the remaining sauce over the top layer of potatoes.
• Cashew Substitutes: You can try the typical cashew substitutes: silken tofu, white beans, other nuts, or seeds with the understanding that the flavor and texture will change accordingly.  You may need to adjust/add ingredients to compensate.   We have not tested any substitutions.
• Cayenne Pepper: The cayenne pepper is subtle and adds great flavor without adding heat. We loved it. We do not recommend leaving it out.
• Resting Period: Do not skip the 15 minutes resting period. The potatoes will continue to cook a little, but as they slightly cool, they will absorb most of the flavorful broth.  The flavor will continue to develop during this 15-minute resting period.  The longer the dish sits, the more liquids are absorbed into the potatoes which then becomes more flavorful.
• Table Salt: If using table salt, you should use less table salt than the amount listed in the ingredients as sea salt crystals are larger than table salt crystals. Since table salt crystals are very fine, less table salt is required to season a dish. We would suggest starting with about 1/4 to 1/2 the amount of sea salt listed. You can always add more salt but cannot take it away. We recommend using sea salt as it is less refined than table salt.

Leftovers and Freezing:

Leftovers will generally keep 4 days in the refrigerator.  Store in a covered container.

This dish can be frozen.

Pantry Products:

• Vegetable Stock: We use Pacific Organic Low Sodium Vegetable Stock. We love this brand because it is Whole Food Plant Based compliant, as it does not contain MSG, has no oil, and does not contain any highly-processed ingredients.  Feel free to use your favorite vegetable broth.
• Tamari: We used San J Tamari Soy Sauce, Gluten Free, Reduced Sodium. You can substitute the tamari with reduced sodium soy sauce, Braggs Liquid Aminos, or Braggs Coconut Liquid Aminos. We recommend using reduced-sodium products.
• Sea Salt: Please adjust the sea salt based upon your family’s sea salt preferences and/or based upon dietary needs.

Kitchen Equipment:

• Large skillet with a tight-fitting lid
• High-Speed blender
• Stock pot to par-boil the potatoes
• Small casserole pan (no larger than 9 x 13)

If you try this comforting dish, we would love to know if you enjoy it as much as we do! Please leave us a review! Post a picture on Facebook or Instagram and tag us! We would love to hear from you.

Vegan Mushroom and Onion Scalloped Potatoes

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• Author: Monkey and Me Kitchen Adventures
• Prep Time: 30 Minutes
• Cook Time: 35 Minutes (+Rest Time)
• Total Time: 65 Minutes (+Rest Time)
• Yield: 4 to 6 1x
• Category: Dinner, Side
• Method: Stovetop, Oven
• Diet: Vegan

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Description

Rich, velvety, and bursting with the savory goodness of onions and mushrooms, this Vegan Mushroom and Onion Scalloped Potatoes is a true crowd-pleaser that will elevate any dinner or holiday spread.

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Ingredients

Scale 1x2x3x

Potato Boil Ingredients:

• 24 oz. peeled and thinly sliced potatoes *
• ½ to 1 teaspoon sea salt (+/-) * 

Skillet Ingredients:

• 2 medium yellow onions, quartered, thinly sliced *
• 1 Tablespoon minced garlic
• 10 oz. Baby Bella mushrooms, thinly sliced *
• 2 Tablespoons reduced sodium tamari *

Sauce Ingredients:

• 1 cup [raw] cashews *
• 1 cup low-sodium vegetable broth *
• ¾ cup unsweetened plain plant milk
• ¼ cup water
• 1 Tablespoon distilled white vinegar
• ¼ cup nutritional yeast
• 1 teaspoon onion powder
• 1 teaspoon garlic powder
• ¼ teaspoon black pepper (+/-)
• ¼ to 1 teaspoon sea salt (+/-) *
• Pinch cayenne pepper *

Optional Ingredients:

• 3 cups chopped fresh baby spinach *

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Instructions

1. Preheat the oven to 425 F, center rack.
2. Place the cashews into a small bowl, cover with boiling water and allow to sit for 15 minutes, then discard the water, and set aside until Step 6.
3. Peel and thinly slice (about ¼ inch thickness) the potatoes, place into a stock pot, cover with cold water, add the sea salt, and bring to a boil, as soon as the water starts to boil, immediately reduce the heat to a gentle boil. Gently boil for 5 minutes, then immediately drain off the water, and gently rinse in cold water (to prevent further cooking and to set the starches in the potatoes) and set aside until Step 7.
4. In a large skillet, add the finely sliced onions, sauté over medium-high heat for 7 to 9 minutes to soften, add a splash of water, if needed, to avoid burning. Then lower the heat to medium, add the minced garlic, sauté, stir constantly for one minute.
5. Then add the sliced mushrooms and tamari to the skillet with the onions and garlic, stir well, then turn up the heat, sauté for 2 minutes, then lower the heat to a medium. Cover with a tight-fitting lid and allow the mushrooms to reduce in size, approximately 5 minutes. Once reduced, add the chopped baby spinach (if adding) and sauté just until wilted. Remove the onions, mushrooms, and spinach from the skillet, set aside.
6. In the meantime, place the soaked cashews and all the remaining Sauce Ingredients into the high-speed blender, blend on high until smooth and emulsified, the add the sauce to the now empty skillet, cook until hot and bubbly, approximately 2 to 3 minutes, then remove from the stove.
7. Place about ¾ cup of the sauce mixture on the bottom of a casserole dish. Divide the potatoes in half. Place layer half the potatoes in a single layer on the bottom of the casserole dish. Then put some of sauce over top of the potatoes. Then layer all the sauteed mushrooms, onions, spinach mixture, spread it out evenly. Place more of the sauce on top, then layer the other half of the par-boiled sliced potatoes in a single layer on top. Then pour all the remaining sauce over top of the par-boiled potatoes. Gently press down.
8. Cover tightly with foil, then place into a preheated 425 F oven (center rack) and bake for 30 minutes. Remove the foil, test for potato tenderness by piercing the potatoes with a sharp knife. The knife should slide easily.
9. Once the potatoes are tender (turn off the oven); however immediately place the back in the oven, uncovered for 5 minutes, then remove from the oven and allow to sit for 15 minutes to set up before serving.

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Notes

*Please reference the blog post for Tips for Success, Pantry Items Used, Storage and Freezing, and Kitchen Products Used.

*Sea Salt:  Please adjust the sea salt based upon your family’s sea salt preferences and/or based upon dietary needs.

*Servings:  4 to 6

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