This Keto Italian Sub Sandwich Casserole has all of your favorite sub flavors and even a crispy bread topping! It's low-carb, gluten-free, and super easy to make. You're going to love it!
This Keto Italian Sub Sandwich Casserole recipe is one from our cookbook! We're so excited to be sharing it with you today after you guys made it unanimously clear on Instagram that you wanted the recipe! We also recently shared another recipe from the book, our Keto Schnitzel so be sure to check that one out too.
And, if you're interested you can grab the cookbook on Amazon or wherever books are sold and have 73 more delicious one-pan complete dinner recipes at your fingertips.
This casserole is one of our absolute favorites! It's also great for beginners as it's rich, filling, and super easy to make. We make this at least once a month, the leftovers are SO good cold, trust us!
Ingredients in Keto Italian Sub Sandwich Casserole
The filling is a mixture of shaved sugar-free deli ham, capicola, salami, and pepperoni. For the vegetables, we go with green bell peppers, tomatoes, olives, onions, and Italian seasonings with a drizzle of olive oil and a splash of red wine vinegar. The crust is basically Fat Head dough that we roll out into a crust. It's like a sub sandwich and a pizza had a casserole baby and it is GOOD.
You can serve it as is as a complete meal but we especially love serving the casserole on top of some seasoned and shredded lettuce. We typically toss the lettuce (usually Romaine) with olive oil, salt, pepper, and another splash of red wine vinegar. Totally optional though!
If you give it a try, tag us on IG @castiron_keto and leave a comment below! We love seeing and sharing your CIK creations!

📖 Recipe
Italian Sub Sandwich Casserole
Ingredients
Crust:
- 1 ½ cups shredded mozzarella part-skim / low moisture (170g)
- ⅔ cup almond flour 66.7g
- 2 egg whites 66g
- 1 teaspoon xanthan gum optional (3g)
Casserole Filling:
- ½ lb sliced deli ham 227g
- 8 slices salami 24g
- 8 slices pepperoni 24g
- 8 slices capicola 24g
- 13 slices provolone cheese 364g
- 1 bell pepper thinly sliced (119g)
- 2 Roma tomatoes diced or sliced (124g)
- 1 cup pitted black or kalamata olives 227g
- ¼ medium red onion thinly sliced (25g)
- ½ cup pickled banana peppers 113g
- 2 tablespoons olive oil 27g
- 1 tablespoon red wine vinegar 14.9g
- 1 tablespoon Italian seasoning 3g
Instructions
- Preheat the oven to 400° F.
- In a medium mixing bowl melt the mozzarella in the microwave just until melted, about 30 seconds.
- Stir in the remaining dough ingredients into the mozzarella.
- Roll into a ball and knead 1 or 2 times. Place the dough between 2 sheets of parchment paper. Using a rolling pin roll the dough out to a 10.5” circle about ½ ” thick.
- Layer the remaining ingredients into a 10.5” skillet in this order: ham, salami, pepperoni, capicola, 1⁄2 the provolone, bell pepper, tomato, olives, red onion, and banana peppers.
- Drizzle the olive oil, red wine vinegar, and Italian seasoning over the top then top with remaining cheese then top with the crust.
- Transfer to the oven and bake 25-30 minutes until the crust is browned. Serve immediately.
Katie S. says
So good! We've made 3 of your recipes three nights in a row and hot dang they're delicious!
Lisa says
That looks fun and delicious!
Dottie says
We just love this! Reminds us of the baked hoagies from Pennsylvania. Flavor bomb and so easy to make. Thank you for this recipe!
Allen says
I love this recipe!!! Flavor is amazing. My only issue is with the amount of moisture produced that has to be bled off. This isn’t my first rodeo and yet after placing all the water laden veggies in paper towels prior to assembly, I still get about a cup of liquid that has to be poured off. I realize that we are working with very fatty meats and that they are rendered in the casserole. I just think it should be mentioned, that’s all. Again, love the flavors!!! I miss my Italian subs and this fills the void.
Sureve Everus says
Whole family loves this. I often use the topping for just making regular sandwiches on or to top other keto casseroles.