Keto Spinach Casserole (Boston Market–Inspired Comfort Food)

A creamy keto spinach casserole inspired by the classic Boston Market favorite—without the carbs.

A creamy low-carb side dish that brings back a classic favorite—without the carbs

If you ever loved Boston Market's spinach casserole, this keto version will feel like a little trip back in time. Creamy, savory, and comforting, this dish delivers everything you remember—without flour, sugar, or high carbs.

This keto spinach casserole makes an excellent side dish for chicken, turkey, pork, or any simple skillet meal. It’s also easy to adapt if you prefer a dairy-free keto approach, which I’ve included below.

Why This Keto Spinach Casserole Works

Boston Market’s version was smooth, slightly onion-forward, and rich without being heavy. This keto-friendly version recreates that texture by focusing on well-drained spinach, slow-cooked onions, and a creamy base—without breadcrumbs or thickeners that spike blood sugar.

It reheats well, making it perfect for meal prep or holiday meals.

Ingredients (Serves 6)

Base

16 oz frozen chopped spinach, thawed and squeezed very dry

2 tablespoons olive oil or avocado oil

½ cup finely chopped onion

1 clove garlic, minced (optional)

Creamy Base (choose one)

Traditional Keto (occasional dairy)

4 oz cream cheese, softened

½ cup heavy cream

½ cup shredded cheddar or mozzarella (optional topping)

Dairy-Free Keto Option

¾ cup full-fat canned coconut milk

2 tablespoons almond butter or cashew butter

1 tablespoon nutritional yeast

Seasonings

½ teaspoon salt (or salt substitute, to taste)

¼ teaspoon black pepper

Pinch of nutmeg (optional but authentic)

Instructions

Prepare the spinach

Thaw the spinach and squeeze out as much liquid as possible. This step is essential for a thick, casserole-style texture.

Sauté the aromatics

Heat oil in a skillet over medium-low heat. Add the chopped onion and cook over low heat until soft and lightly golden, about 8 minutes. Add garlic, if using, and cook for 30 seconds.

Create the creamy base

For the dairy version, stir in cream cheese until melted, then add heavy cream.

For the dairy-free version, whisk together coconut milk, nut butter, and nutritional yeast before adding it to the skillet.

Combine

Fold in the spinach, salt, pepper, and nutmeg. Cook for 2–3 minutes until thick and well combined.

Bake

Transfer the mixture to a greased baking dish. Add cheese on top if using.

Bake at 375°F for 20–25 minutes, until hot and lightly golden.

Rest before serving

Let the casserole rest for 10 minutes to set and thicken naturally.

Tips for the Best Texture

Chop the spinach extra fine if you prefer a smoother casserole.

Letting it rest after baking makes it easier to serve

This dish thickens even more as it cools, making leftovers excellent.

Serving Ideas

This keto spinach casserole pairs beautifully with:

Ground turkey steaks and gravy

Baked chicken or pork loin

Simple cabbage skillet meals

Holiday keto spreads as a low-carb vegetable side.

This recipe delivers classic comfort without compromising your keto lifestyle. Whether you make it with dairy or choose the dairy-free option, it’s a reliable side dish you’ll come back to again and again.

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