Vegetable Casserole Bake Recipe

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Layers of spaghetti squash, caramelized mushrooms and onions, and fresh spinach meld together in this delicious casserole. Simple yet elegant to serve as either a main or a side dish at a vegetarian dinner party, if desiring to make it completely vegan, substitute out the cheese for a rice or soy-based vegan version.

Vegetable Casserole Bake
Yield: 4

Vegetable Casserole Bake

Prep Time: 15 minutes
Cook Time: 45 minutes
Total Time: 1 hour


  • 1 tbsp olive oil
  • 1 large onion, chopped
  • 2 cups mushrooms, sliced
  • 3 garlic cloves, roughly chopped
  • 1 tbsp fresh thyme
  • 2 cups spinach, fresh
  • 1 large zucchini, sliced
  • 1 cup cooked spaghetti squash
  • 1 1/3 cups shredded mozzarella


  1. Preheat the oven to 375 degrees Fahrenheit. Toss the onion, garlic, mushrooms and thyme together in a deep-bottomed frying pan. Set on the stove at medium-high heat. Fry for 3 to 5 minutes, or until golden brown and fragrant.
  2. Lightly brush the inside of a square or rectangular baking dish with olive oil. Line the bottom with the sliced zucchini and place the fresh spinach evenly over it. Sprinkle ⅓ cup of mozzarella on top. Spoon the onion mix on the mozzarella. Sprinkle another ⅓ cup of mozzarella on top. Layer the spaghetti squash evenly on the mozzarella. Sprinkle the remaining mozzarella on top of the casserole.
  3. Insert the dish into the oven. Bake for 30 to 45 minutes, or until the cheese is brown and bubbling on top.


Calories: 185.5
Fat: 10g
Carbohydrates: 17g
Protein: 10g

Nutrition Information



Serving Size


Amount Per Serving Calories 193Total Fat 10gSaturated Fat 4gTrans Fat 0gUnsaturated Fat 5gCholesterol 19mgSodium 269mgCarbohydrates 17gFiber 5gSugar 6gProtein 12g

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Vegetable Casserole Bake

  • Samantha Lowe

    Based in Kingston, Canada, Samantha Lowe has been writing for publication since 2006. She records her culinary and globe-trotting experiences online at A love of photography and cooking fuels this writing, with the end result usually enticing friends and acquaintances to 'loosen their belts'.

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