Cooking, Baking & Cocktail Shaking

Sausage Pizza Au Gratin Potato Casserole

This Sausage Pizza Au Gratin Potato Casserole is the best of both worlds. It’s pizza. It’s a casserole. It’s a potato dish.

Sausage Pizza Au Gratin Potato Casserole

Today I’m featuring a simple casserole recipe that combines my two favorite food groups: pizza and potatoes.


All snuggled up and cozy.

Sausage Pizza Au Gratin Potato Casserole

I don’t have children of my own, but I’m willing to bet the kiddos will love this casserole. If I were kid, I’d coming running at the very mention of pizza and potatoes.

One of my favorite fall side dishes is creamy, cheese-y au gratin potatoes. I took that concept and put my own very delicious spin on it by turning it in to a main dish.

Sausage Pizza Au Gratin Potato Casserole

Think everything pizza meets cheese-y potatoes.

Sausage Pizza Au Gratin Potato Casserole

I combined my favorite pizza toppings to create a hearty mixture that tastes just like you’re eating a slice of pizza dripping with extra cheese. I used a combination of sausage, mushrooms, onions, and green peppers that I sautéed with Idaho® red potatoes. I chose red potatoes for this recipe because their high moisture center and waxy exterior hold up better when pan fried and baked with the pizza sauce. Even after the casserole is baked, the potatoes stay firm.

Sausage Pizza Au Gratin Potato Casserole

This Sausage Pizza Au Gratin Potato Casserole went straight to my parents after it came out of the oven. The casserole quickly disappeared, and I received texts later that evening requesting a second casserole.

Sausage Pizza Au Gratin Potato Casserole

I combined my favorite pizza toppings to create a hearty mixture that tastes just like you’re eating a slice of pizza dripping with extra cheese.

Yield: 1 (9-inch-by-13-inch) casserole

Total Time: 1 hour 15 minutes

Prep Time: 15 minutes

Cook Time: 1 hour


  • 1 pound ground hot Italian sausage
  • 3 tablespoons olive oil, divided
  • 8 ounces sliced baby Portobello mushrooms
  • 5 red potatoes, cut into ½-inch cubes (about 5 cups)
  • 1 large onion, chopped
  • 1 green pepper, chopped
  • 2 cloves garlic, minced
  • 1 teaspoon red pepper flakes
  • 1/2 teaspoon dried Italian seasoning
  • 1 (28-ounce) can pizza sauce
  • 1/4 cup grated Parmesan cheese
  • 2 cups mozzarella cheese, divided
  • 1/4 cup chopped parsley for garnish
  • Salt and pepper


  1. Preheat oven to 350 degrees F. Lightly grease a 9-inch-by-13-inch casserole dish.
  2. Heat a large skillet over medium-high heat. Add the sausage to the and cook, breaking up the meat as you go along, until brown, about 7-10 minutes. Using a slotted spoon, transfer the sausage to your prepared casserole dish.  
  3. Add 1 tablespoon of olive oil to the pan. Stir in the mushrooms. Continue to cook, stirring occasionally, until tender and brown, about 5 minutes. Refrain from seasoning with salt until the end of the cooking process. Transfer the browned mushrooms to the casserole dish with the sausage.
  4. Add the remaining 2 tablespoons of olive oil to the pan. Stir in the potatoes. Season with a generous pinch of salt and pepper. Cook, stirring occasionally, for 12 minutes.
  5. Add the onion, green pepper, garlic, and red pepper flakes to the pan with the potatoes; stir to combine. Continue to cook, stirring often, until the potatoes are fork tender, about 10 minutes.
  6. Stir in Italian seasoning, pizza sauce, Parmesan cheese, and 1 cup of mozzarella. Continue to cook for 3 minutes. Season with salt and pepper to taste.
  7. Transfer the mixture to the prepared casserole dish with the sausage and mushrooms; stir to combine. Top with the remaining mozzarella cheese. Bake for 30 minutes uncovered. Sprinkle with fresh parsley, if desired.

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Disclosure: This recipe was developed for the lovely folks at Idaho® Potato. All opinions are my own. Thank you for supporting my recipes and site while I work with brands I adore.

19 Responses to “Sausage Pizza Au Gratin Potato Casserole”

  1. #
    Taylor @ Food Faith Fitness — September 14, 2015 at 8:37 am

    Pizza and potatoes all snuggled up definitely sounds like my idea of YUM.  I want this casserole for breakfast, lunch and dinner today! Pinning!


    • Jennie replied September 14th, 2015 at 8:45 am

      Thanks so much, Taylor! 


  2. #
    Karly — September 14, 2015 at 8:52 am

    Pizza and potatoes. I can get down with that!


    • Jennie replied September 14th, 2015 at 9:08 am

      Yes, that’s the spirit! Thanks, Karly. 


  3. #
    Anita at Hungry Couple — September 14, 2015 at 11:02 am

    This is gorgeous and mouthwatering and I want to eat it RIGHT THIS MINUTE!


    • Jennie replied September 14th, 2015 at 2:11 pm

      Thank you, Anita! You’re always welcome over for dinner. 


  4. #
    Ashley — September 14, 2015 at 1:45 pm

    Pizza + potatoes is definitely the ultimate comfort food! This sounds wonderful – perfect for the chilly weather that will hopefully arrive soon! haha Can you tell I’m done with the heat???


    • Jennie replied September 14th, 2015 at 2:12 pm

      The cooler weather is slowly (too slow if you ask me) creeping in here in Baltimore. I am so ready for sweater weather, pumpkin everything, and bonfires. Thanks so much, Ashley!


  5. #
    Lauren @ Healthy Delicious — September 14, 2015 at 9:52 pm

    That looks like a big ole pan of comfort, right there!


    • Jennie replied September 15th, 2015 at 8:26 am

      Thanks, Lauren!


  6. #
    Julia — September 16, 2015 at 9:55 am

    Pizza + potatoes = the casserole of my dreams! I’m envisioning a constant supply of this casserole in my refrigerator to make lunch/dinner/snack the most delicious experience ever. On repeat. In excess. Need it all in my face!


  7. #
    nicole ~ Cooking for Keeps — September 16, 2015 at 3:12 pm

    Totally obsessed with this!  Potatoes + pizza = love. 


  8. #
    Annie @ Annie's Noms — September 17, 2015 at 7:52 am

    Oh man, this looks divine! I need this in my life, so I can faceplant the whole pan! 


  9. #
    Carla — September 17, 2015 at 4:50 pm

    I can’t wait to try this pizza potato casserole myself!


  10. #
    Jessica @ A Kitchen Addiction — September 18, 2015 at 10:40 am

    What a great combination of flavors! This is some great comfort food!


  11. #
    Lori @ Foxes Love Lemons — September 22, 2015 at 10:02 am

    No kids here either, but I’m pretty confident that kids of all ages would love this. In fact, if I had a functioning kitchen, I’d be making this for my niece’s 4th birthday this weekend. But instead, you get a hug, some board games, and an IOU for a cheesy casserole, kiddo. Give me a big scoop of this, a little salad on the side, and I’d be so happy!


  12. #
    Susan — September 22, 2015 at 12:18 pm

    How do we get on the pizza potato casserole delivery service because I want in on that! This is the perfect meal with enough to have leftovers for a few days.  Forget the kids, this adult wants in! 


  13. #
    Courtney @ NeighborFood — September 22, 2015 at 12:44 pm

    Well hello there comfort food. Let me just grab my fork and you can just hand the casserole dish over!


  14. #
    Jackie — December 29, 2016 at 3:27 pm


    What brand of pizza sauce did you use in this recipe.


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