This wholesome mushroom and lentil pie is a vegan and gluten free twist on shepherd’s pie! Featuring a bed of lentils, mushrooms, and a mirepoix of veggies in a rich and full-bodied gravy. Then topped with creamy mashed potatoes!

Casseroles are a special kind of comfort food that we often reserve for colder weather, but make-ahead dishes like this should be enjoyed all year long, in my humble opinion.
This dish was inspired by my lentil shepherd’s pie but features a glossy and rich gravy, instead of a tomato-based base. Make this dish even easier using my Instant Pot (no drain) mashed potatoes!
Jump to:
Is it healthy?
You bet! Here are some reasons why.
- This mushroom and lentil pie is very low in fat, using no oil or butter. (Not even in the mashed potatoes.)
- It’s low in calories, but high in protein and fiber for a complete meal that is satisfying, but wholesome.
- Nutrient dense from lentils and a variety of fresh vegetables.
- No puff pastry! Rather than a puff pastry top that’s loaded with butter and refined flour, I’m using creamy mashed potatoes for the topping!
Ingredients + Substitutions
Here’s what you’ll need.
- Brown lentils: You may sub for green if that’s what you have on hand. But don’t use red as they don’t hold up as well and may turn to mush.
- Mushrooms: I prefer cremini or baby bella vs white for their heartiness.
- Potatoes: My first choice for mashed potatoes is always Yukon Gold for their rich and creamy texture. You may sub for russet if you prefer, which will yield less dense, fluffy mashed potatoes.
- Broth: Use a flavourful vegetable broth, such as my homemade version for best results.
- Red wine: This adds richness and depth of flavour to your gravy. If you’re avoiding alcohol you may sub for additional broth.
- Soy milk: To mash into your potatoes, use any dairy free milk you have and prefer.
- Flour: To thicken your gravy. I like white whole wheat flour, but use brown rice flour for gluten free, if needed.
Instructions
(This is a summary with step by step photos, full recipe measurements and instructions are in the recipe card below.)
If cooking your lentils from scratch, sort and rinse them, then add them to a pot of water and get those cooking. (photo 1)
Meanwhile, cook your quartered potatoes on the stovetop OR in your Instant Pot for hands-off. Once cooked mash them using a potato masher and add the milk and salt to taste. Set aside. (photos 2-6)
Sauté the onion, carrot, celery, and garlic in a deep skillet with a tablespoon or so of water or broth, as needed to prevent sticking. Cook until soft, approx. 7-10 minutes. (photos 7-8)
Add the mushrooms and cook until reduced, approx. 5 minutes. (photos 9-10)
While the veggies are cooking, whisk together the broth, flour, wine, balsamic, and seasoning. (photos 11-12)
Then add the mixture to your veggies and cook until thickened, approx. 5 minutes. (photo 13)
Transfer the cooked lentils and vegetables with their gravy to your casserole dish. Mix well. (photos 14-16)
Then scoop the mashed potatoes on top and spread as evenly as you can with a silicone spatula. (photo 17)
OPTIONAL: Use a fork to create a crisscross pattern on top of your mashed potato layer. This will help your potatoes crisp up in the oven if desired. Then bake for 20-25 minutes. (photos 18-19)
Once baked, let your pie rest at room temperature for a few minutes to help set a little, and then dig in!
Can I make in advance?
Yes. You may fully prep your ingredients and assemble your pie ahead of time. Wrap tightly and then pop it in the refrigerator to bake within the next 1-2 days. Add 10 minutes to bake time to ensure the pie is heated all the way through.
Which wine to use?
My personal favourite is a cabernet sauvignon. It’s very rich and robust in flavour and not so sweet, so it works well in savoury dishes.
Storage
Store leftovers in your refrigerator for 3-4 days. You may reheat the pie in the oven, or heat a deconstructed version on the stovetop. (I love it deconstructed!)
You may freeze an entire pie before baking if you’re making it in advance. Then thaw in the refrigerator overnight and bake covered in foil for 30-40 minutes, removing the paper for the last 5-10 minutes to brown the top.
Expert tips
- Don’t overcook your lentils as they’ll continue cooking in the oven and you don’t want them to turn to mush.
- Use broth over water to cook your lentils and your potatoes for added depth of flavour.
- For the wine (if using), make sure to use a good quality wine that you enjoy. If you don’t like the flavour for drinking, it’s not good enough for cooking with, either.
More dishes you’ll love
If you tried this recipe, please let me know about it in the comments below. I always love hearing from you! Don’t forget to Subscribe to This Healthy Kitchen to be among the first to get my new recipes! You can also FOLLOW ME on Facebook, Instagram, Pinterest and Twitter to see more delicious food and get all the latest updates.
Buon appetito
Rosa
📖 Recipe
Equipment
Ingredients
Mashed Potatoes
- 3 pounds Yukon Gold potatoes peeled (if desired) and quartered
- ½ cup soy milk or plant milk or choice
- sea salt to taste
Filling
- 1 cup brown lentils or 3 cups cooked or canned
- 4 cups water for cooking the lentils if you're not using canned (you may also use broth for added flavour)
- 1 yellow onion diced
- 2 carrots peeled + diced
- 2 ribs celery diced
- 4 cloves garlic peeled + minced
- 8 ounce mushrooms sliced
- 2 cups vegetable broth
- ¼ cup white whole wheat flour or brown rice flour for gluten free
- 1 tablespoon balsamic vinegar
- ¼ cup red wine
- ¼ teaspoon dried thyme
- ¼ teaspoon dried sage
Instructions
Mashed Potatoes
- If you have an Instant Pot you may use this Instant Pot method to make your mashed potatoes. If you don't have an Instant Pot, add your quartered potatoes to a pot and fill with salted water, covering 1 inch above the potatoes. Bring to a boil, and then lower heat to maintain a low boil and cook until fork-tender. Approx. 15-20 minutes. Once cooked, drain and return the potatoes to the pot. Mash them using a potato masher, add the milk and mix well. Taste for salt, add more if necessary, and set aside.
Filling
- Meanwhile, sort through your lentils, discarding any small rocks, and rinse them well in a colander. Then place the lentils with 4 cups of water and a teaspoon of salt (or use broth for added flavour) in a small saucepot. Bring to a boil, then reduce heat and simmer for 20-22 minutes. Don't overcook your lentils as they'll continue cooking in the oven. Drain and set aside.
- Use a large, deep pan to sauté the onion, carrot, celery, and garlic until soft, approx. 7-10 minutes. Then add the mushrooms and cook until reduced, approx. 5 more minutes.
- While the veggies are sauteéing, use a bowl or large measuring cup to whisk together the 2 cups of broth, flour, balsamic, red wine, thyme, and sage. Then pour it into the pan with the sautéed veggies. Cook, stirring often until your gravy is slightly thickened, approx. 5 minutes.
Assembly + Bake
- Preheat the oven to 400 degrees F. Then transfer the cooked lentils and sautéed vegetables with the gravy to your casserole dish and mix well. Top with the mashed potatoes and use a fork to create a crisscross pattern, if desired. This will make the top layer crispier when baking. (See process shots above.)
- Bake your pie for 20-25 minutes, until the top is golden brown. Then remove from the oven and let rest for a few minutes before serving.
Diana🇳🇱
It was very delicious. What is the serving size that corresponds with 265 calories what you mentioned under nutrition? Thank you for your recipe.
Rosa
Glad you enjoyed it. The nutritional info is for 1/8 of the casserole.
Heather
I made this for Thanksgiving for my husband and myself. So good! And leftovers the next day were just as good, maybe even better. Already planning on making this ahead of time for Christmas dinner since we’ll be traveling. 😋
Rosa
That’s wonderful Heather. Thanks so much for taking the time to leave a review. 🙂
Joan
One of the most delicious recipes I have ever made. One of my favorites. I prepare the lentils a day or two before so there is less prep time and use vegetable broth. I also add extra mushrooms to the mixture (we love mushrooms). I also buy the River Gold ready to steam potatoes (2 bags) which makes it easier. This is actually even better the next day as leftovers. I love all of your recipes. I am so glad I found you. Thank you,
Rosa
Wow thanks for the lovely review Joan! Thrilled you enjoyed it. 🙂
Kelly D
I prepped this for dinner tonight on my lunch break and I will say it is quick and easy to come together. Flavors so far are very good! Thank you for the recipe and I look forward to dinner tonight!!
Rosa
Thanks very much for the review Kelly! 🙂
Sharon
First time….Delish!!!!…. will make again……It is very helpful to also have the ingredients in weight measures as two nantes carrots are very different from others. It helps me when I input recipes like this into MyFitnessPal to get the numbers I need. Again excellent!
Rosa
Absolutely thrilled you enjoyed Sharon!
Tony M
Delish… everyone liked it. Made it exactly as stated in the recipe except a splash more milk in the mashed potatoes.
Rosa
Thrilled to hear that Tony. 🙂