This Ham Cheese and Onion Puff Pastry Slab Pie is a savory dish usually served as a main course. It is made with puff pastry and a filling of slightly caramelized onion, ham, and cheese.
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Ham Cheese and Onion Puff Pastry Slab Pie
Easy to make and delicious, you can serve this pie any day of the week, but you can also make it for times when you entertain, as it works as an appetizer as well.
Elegant enough but also casual, the pie goes well with a refreshing summer salad and veggie/ winter salads, and a glass of light white wine. If you are looking for a variation from the classic “meat and potatoes” type of dinner, this recipe is for you.
You can use puff pastry sheets that you can find at any grocery store. I recommend keeping some additional sheets at hand in your freezer for other delicious pie dishes. (see here Minced meat pie).
What is a slab pie? I never heard the term before:
A slab pie is a shallow pie made in a rectangular, rimmed baking sheet. It is bigger and perfect to feed a crowd, creating a fantastic option for your holiday table, a potluck, or when you entertain.
Slab pies usually start with refrigerated pie crusts or puff pastry and can be made savory or sweet. You definitely can’t go wrong with these pies because they pair well with many things. Sometimes, these slab pies, when savory, can serve as appetizers as well.
What is puff pastry?
Puff pastry or pate feuillete or feuilletage in French is a rich and delicate pastry made up of very thin layers of dough and butter.
To make puff pastry from scratch is a lengthy and complicated procedure. Butter is incorporated into a rolled-out dough of flour and water. The dough is then folded, turned at right angles, rolled out, and folded again.
This procedure is repeated several times, and the dough is left to stand and chill between each turning. The more turns there are up(up to eight, usually, according to Larousse Encyclopedia), the greater the number of layers in the finished pastry.
Because of the long process, almost nobody makes this pastry from scratch anymore, so don’t feel bad if you buy it in the store. Even famous chefs don’t waste their time making it from scratch.
Note: Puff pastry is usually not sweetened, and it is used for pies, tarts, pastries, and many other dishes. It is usually baked at high temperatures, so the air, trapped during rolling, expands.
The melting fat content and heat set the layers and give the pastry the characteristic crisp texture.
How to make Ham Cheese and Onion Puff Pastry Slab Pie:
Step 1.
Preheat oven to 400F/200C.
Step 2.
Defrost the puff pastry for no more than 40 minutes at room temperature; otherwise, it will be simply hard to work with it.
Step 3.
Slice the onion thinly and dice the ham.
In a large skillet, heat the butter or the oil and add the onions and ham.
Step 4.
Cook onions until they are soft and slightly caramelized, about 7-10 minutes. Stir often, so the onions don’t burn.
Step 5.
Add salt, nutmeg, and pepper. Taste and make sure the amount of salt is enough. If not, add a little bit more.
Step 6.
Remove from the heat and let the mixture cool for a few minutes.
Step 7.
Beat three eggs and add them to the mixture.
Also, add the shredded cheese.
Note: Cheddar cheese works perfectly, but there is no rule to add whatever shredded cheese you have around.
Maybe you want to mix cheddar cheese with a bit of gruyere, or perhaps you have a bag of Mexican cheese or even Feta cheese. Suits well!
Stir to combine.
Step 8.
In a 9×13 inch baking pan, place a puff pastry sheet on the bottom of the pan.
Step 9.
Add the mixture of onions and ham and spread it evenly over the puff pastry sheet.
Step 10.
Cover the mixture with the second puff pastry sheet and tuck the edges of the puff pastry inside the tray.
Step 11.
Beat an egg and brush the entire surface of the pie with it.
Also, grab a fork and poke the puff pastry top everywhere.
Step 12.
Bake at 400F/200C for about 35 minutes or until golden brown.
Slice it in squares and serve it warm.
Can I make this recipe in advance?
If you want to make this recipe in advance, you can put it together and then freeze it. On the day of serving it, heat the oven and bake it.
What about leftover? How long they last in the fridge? Can I freeze them?
You can reheat it in the microwave or the oven for a few minutes. I do not recommend freezing the leftovers as the pastry will get soggy.
Leftover pie should be good in the fridge for a maximum of 3-4 days.
Can I use pie crust instead of puff pastry?
Yes, you can. However, the puff pastry texture is very different from the pie crust one, but if you like that better or don’t have access to puff pastry, go ahead and use what you have. Keep in mind that the two are not the same, so that the results will be quite different.
I don’t have ham, can I use something else?
Ok, if you don’t have ham, buy some. However, you can replace the ham with sausages, like kielbasa style, or cooked steak.
I don’t like onions, what else can I use?
You might be surprised how many people ask this question. Leeks would be a good option if you hate onions, but keep in mind that they are from the same family of vegetables. Leeks are also sweeter and have a slightly different texture.
Bon appetite!
Suggestion for a sweet slab pie:
Suggestions for other recipes that use puff pastry:
Romanian Spinach And Feta Cheese Pie
Ham And Cheese Puff Pastry Pockets
Cabbage puff pastries triangles
Easy recipes made with puff pastry
Ham Cheese And Onion Puff Pastry Slab Pie

This Ham Cheese and Onion Puff Pastry Slab Pie is a savory dish usually served as a main course. It is made with puff pastry and a filling of slightly caramelized onion, ham, and cheese.
Ingredients
- 17.25oz puff pastry (one package with 2 puff pastry sheets)
- 3 large onions(2 white, 1 red) sliced thinly
- 4 tablespoons butter or olive oil
- 16 oz cooked ham diced
- 1/2 teaspoon nutmeg
- 1/2 teaspoon salt
- 1/2 teaspoon ground peppers
- 3 large eggs for the filling
- 1 large egg for brushing the pastry
- 8 oz shredded cheese(Cheddar, Mozzarella, Monterey Jack, crumbled Feta etc)
Instructions
- Preheat oven to 400F/200C.
- Defrost the puff pastry according to the package. (Do not let it sit at room temperature for more than 40 minutes. More than 40 mins sitting at room temperature, and the puff pastry will be difficult to work with.)
- While the puff pastry is defrosting, slice the onions thinly and dice the ham.
- In a large skillet, heat the butter or the oil and add the onions and ham. Cook them until the onions are soft and slightly caramelized, about 7-10 minutes. Stir often, so the onions don't burn.
- Add salt, nutmeg, and pepper. Taste and make sure the amount of salt is enough. If not, add a little bit more.
- Remove from the heat and let the mixture cool.
- Beat the 3 eggs and add them to the mixture. Also, add the shredded cheese. Stir to combine.
- In a 9x13 inch baking pan, place a puff pastry sheet on the bottom of the pan.
- Add the mixture of onions and ham and spread it evenly over the puff pastry sheet.
- Cover the mixture with the second puff pastry sheet and tuck the pastry's edges inside the tray.
- Beat an egg and brush the entire surface of the pie with it. Also, grab a fork and poke the puff pastry top everywhere.
- Bake at 400F/200C for about 35 minutes or until golden brown.
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Nutrition Information:
Yield:
15Serving Size:
1Amount Per Serving: Calories: 359Total Fat: 25gSaturated Fat: 8gTrans Fat: 0gUnsaturated Fat: 15gCholesterol: 95mgSodium: 610mgCarbohydrates: 18gFiber: 1gSugar: 1gProtein: 15g