If you’re anything like us, green bean casserole probably made an appearance at just about every holiday table growing up. In fact, it’s the first thing I go for when I’m cruising the Thanksgiving table. That creamy, savory filling paired with those crispy onions on top? Total comfort food.
But if you’re skipping dairy—or cooking for someone who is—you might be wondering if you have to say goodbye to this classic side. The answer is, you absolutely don’t!
This dairy-free green bean casserole delivers all the cozy, nostalgic flavor you love, minus the milk, cream, and canned soup.
We’ve given this dish a bit of a power-up with fresh green beans, a from-scratch mushroom sauce, and a crispy topping that doesn’t rely on processed ingredients. It’s warm, creamy, and totally crowd-pleasing—whether you’re serving it at Thanksgiving or just craving a comforting veggie-forward dinner.
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Why You’ll Love This Dairy-Free Green Bean Casserole
- Classic taste, made plant-based. Creamy mushroom sauce made with oat or almond milk (or coconut milk if you like it richer) and savory tamari.
- Easily made gluten-free. Use a 1:1 gluten-free flour blend and a gluten-free crispy topping.
- No canned soup required. Homemade mushroom sauce brings bold, clean flavor without additives.
- Perfect for holidays or cozy weeknights. Family-friendly and freezable components.
- Flexible topping options. Go traditional, homemade, or air-fried.
Ingredients You’ll Need
Fresh and Pantry Staples
- green beans (fresh or frozen)
- olive oil or plant-based butter
- yellow onion or shallots
- garlic
- cremini mushrooms
- all-purpose flour (or gluten-free 1:1 blend)
- vegetable broth or stock
- dairy-free milk (oat or almond are best for neutral flavor; coconut adds richness)
- soy sauce or tamari (gluten-free)
- dried thyme
- red pepper flakes (optional)
- Salt and black pepper
- Optional: lemon juice
Crispy Topping Options
- French’s fried onions (check label for dairy/wheat)
- OR homemade crispy shallots or onions
- OR air-fried onions for a lighter topping
How to Make Dairy-Free Green Bean Casserole
Prep the Green Beans
- If using fresh, blanch in boiling water for 3–5 minutes, then transfer to an ice bath to stop cooking. Drain well.
- If using frozen, thaw and pat very dry to avoid a watery casserole.
Make the Mushroom Sauce
- In a large oven-safe skillet (like cast iron), heat oil over medium heat.
- Sauté onions/shallots until soft (about 5 min), then add garlic and mushrooms.
- Cook until mushrooms release their moisture and begin to brown.
- Stir in flour and cook for 1–2 minutes.
- Slowly pour in broth and milk, stirring constantly to avoid lumps.
- Add soy sauce, thyme, pepper flakes, and lemon juice. Simmer 3–5 minutes, or until sauce is thick and creamy.
Tip: If your sauce seems too thin, simmer a bit longer. Oat milk especially benefits from an extra minute or two of reduction.
Assemble and Bake
- Stir in green beans until coated with sauce.
- If using a cast iron or oven-safe skillet, you can bake right in the pan.
- If using a baking dish, transfer the mixture to it.
- Top with crispy onions.
- Bake at 375°F for 20–25 minutes, until bubbling and golden.
Tips and Variations
- Want to save time? Use canned green beans and a store-bought dairy-free mushroom soup like the one from Trader Joe’s.
- Coconut-sensitive? Use oat or almond milk for a neutral taste.
- Gluten-free? Use a 1:1 gluten-free flour like Bob’s Red Mill and choose a GF onion topping or make your own.
- No soy? Coconut aminos work great.
- Lighter version? Air fry onions instead of frying them.
- Flavor boost? Add a splash of white wine while cooking the mushrooms.
Storage and Make-Ahead Tips
- Make ahead: Prepare everything except the topping. Store covered in the fridge up to 2 days. Add topping and bake before serving.
- Leftovers: Keep in a sealed container in the fridge for 3–4 days.
- Reheat: Heat in the oven or air fryer to revive the crispy topping.
Dairy-Free Green Bean Casserole
Ingredients
For the Mushroom Sauce
- 1 tablespoon olive oil or plant-based butter
- 1 small yellow onion or 2 shallots finely chopped
- 2 cloves garlic minced
- 8 oz cremini mushrooms sliced
- 2 tablespoons all-purpose flour or gluten-free 1:1 blend
- 1 cup vegetable broth or stock
- 1 cup unsweetened plant milk
- 1 tablespoon soy sauce or tamari
- ½ teaspoon dried thyme
- ¼ teaspoon red pepper flakes optional
- Salt and black pepper to taste
- 1 tablespoon lemon juice optional
For The Casserole
- 1 lb fresh green beans trimmed and blanched (or frozen, thawed)
- 1½ cups crispy fried onions store-bought or homemade
Instructions
- Preheat oven to 375°F (190°C).
- Blanch green beans in boiling water for 3–5 minutes if using fresh. Transfer to an ice bath, then drain well. If using frozen, thaw and pat dry.
- In a large oven-safe skillet, heat olive oil over medium heat.
- Sauté onions/shallots for 5 minutes. Add garlic and mushrooms, and cook until mushrooms release liquid and begin to brown.
- Stir in flour and cook for 1–2 minutes, stirring constantly.
- Slowly add broth and non-dairy milk while whisking. Simmer 3–5 minutes until thickened.
- Add soy sauce, thyme, pepper flakes, and lemon juice. Season to taste.
- Add green beans and stir to coat in sauce.
- Top with crispy onions. Bake 20–25 minutes, until bubbling and golden.
- Let rest a few minutes before serving.
Notes
- Use “lite” coconut milk for a lighter flavor or swap in oat/almond milk for neutral taste.
- To make ahead, assemble without topping and refrigerate up to 2 days. Add topping before baking.
- For gluten-free: Use certified gluten-free fried onions and flour.
- Want to go all homemade? Try air frying sliced onions tossed in flour for the topping.
Frequently Asked Questions
Can I use canned mushroom soup?
Yes, just be sure it’s dairy-free. We like the one from Trader Joe’s for a shortcut that still tastes great.
What if I need this gluten-free?
Swap in a 1:1 gluten-free flour blend for thickening the sauce, and make sure your crispy topping is certified gluten-free—many store-bought fried onions contain wheat.
Is coconut milk too strong?
It depends on the brand and your personal taste. If you’re unsure, use “lite” coconut milk or opt for oat or almond milk for a more neutral flavor.
Can I make it ahead?
Absolutely! Prep the casserole up to the point of baking, but leave off the crispy topping. Store in the fridge for up to two days. Add the topping right before baking to keep it nice and crisp.
