This halloumi sandwich is a satisfying lunch or quick weeknight dinner option! Halloumi slices and onions are cooked in a grill pan (or skillet) and layered with tomatoes, lettuce, and a tangy garlic mayo. You can make this hearty sandwich in only about 15 minutes!

Have you tried halloumi cheese yet? If not, you need to give it a go! This semi-hard cheese is so special because it can take direct heat well (like from a grill), getting nice and soft without totally turning to a melty puddle. That makes it a great option to serve in a sandwich like this one, layered with other fresh ingredients.
To make this halloumi sandwich, all you need to do is cook the halloumi in a grill pan (or you can use a skillet), along with a couple slices of onion, which get nice and sweet. Then, layer the halloumi and onions with crisp lettuce, ripe tomato, and a tangy garlic mayo.
You can make this delightfully toasty halloumi sandwich in only about 15 minutes, a perfect option for a hearty lunch or satisfying weeknight dinner (paired with a cup of smoky black bean soup, perhaps?)
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Recipe ingredients
Ingredient notes
- Halloumi: you can usually find halloumi sold in small blocks in the "gourmet cheese" section of most grocery stores.
- Bread: use your favorite bread - my recommendation is something hearty and thick-cut, so it will hold up well to grilling and will give structure to the sandwich. I used homemade sourdough here - divine!
- Onion: sweet onion (such as Vidalia) is a very nice option; if you don't have sweet onion, a regular yellow onion will work great too.
Step by step photos
1. First, mix up the mayo topping. All you need to do is stir black pepper, garlic powder, and lemon juice into the mayo and set it aside.
If you like, you can add in a few drops of your favorite hot sauce too!
2. Then, slice the onion and halloumi. Pat the halloumi slices dry, and brush both sides of the halloumi and onions with oil.
3. Add some black pepper to each side too!
4. Grill the halloumi, bread slices, and onions on a grill pan set over medium-high heat for 2 - 3 minutes per side, or, until the halloumi and onions are soft, and you get some beautiful grill marks!
5. Then, spread the flavored mayo on each slice of bread.
6. Now all you have to do is assemble the sandwich. Enjoy it right away while the halloumi is still all nice and soft, yum!
Tips and tricks
- I like using this cast-iron stovetop grill from Lodge (affiliate link); it's large enough that I can cook the onion, halloumi, and bread all at the same time. And, since it's cast-iron I can pre-heat it while I prep the other ingredients without worrying about the finish. (As opposed to non-stick, which should not be heated empty).
- If you don't have a large grill pan, you can grill the ingredients in stages. But, grill the halloumi last so it stays nice and soft when you enjoy your sandwich. If you like, you can keep the bread and onions warm while the halloumi cooks by tenting them loosely with aluminum foil.
- I chose garlic powder to add additional flavor to the mayo. But, if you enjoy the more bracing flavor of fresh garlic, you can substitute ¼ teaspoon of crushed garlic for the garlic powder. Also feel free to add more lemon juice and/or hot sauce to the mayo to customize it to your tastes.
Recipe FAQs
If you don't have a grill pan, you can just as easily cook the ingredients in a skillet, also set over medium-high heat. Just be sure not to move the pieces around while they are cooking so you can get a nice brown crust on the outside!
Yes, you can use an outdoor grill in the same manner as described in the recipe for a stovetop grill pan using medium-high heat, which is about the equivalent of 375 - 450 degrees F. (Here is a nice overview on grilling temperatures if you need more guidance.)
Don't forget to oil the grill grates very well so the halloumi does not stick, and monitor the ingredients well during cooking to make sure they don't burn, since outdoor grills can have hotter and cooler spots.
If you've ever had chewy, rubbery halloumi, you know it's not a very enjoyable experience! There are few factors that will help the halloumi stay soft and tender.
First, make sure to cut the halloumi slices thickly - about ½ inch thick will do. Next, don't overcook the halloumi. It helps to have the grill pan (or skillet) pre-heated well, so you get nice grill marks in only 2 - 3 minutes per side.
And finally, enjoy the halloumi right away while it is still hot off the grill! That's why if you have a smaller grill pan and need to work in stages, make sure to cook the halloumi last.
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PrintHalloumi Sandwich
This is a quick and easy halloumi sandwich recipe that showcases the flavor and texture of the halloumi! Halloumi slices, onions, and bread are cooked on a grill pan (or skillet) and layered with lettuce, tomato, and a tangy garlic mayo.
- Prep Time: 9 minutes
- Cook Time: 6 minutes
- Total Time: 15 minutes
- Yield: 1 serving 1x
- Category: main course, entree
- Method: stove top
- Cuisine: American
Ingredients
- 3.75 ounces (106 g) halloumi cheese, cut into ½ inch thick slices
- 2 onion rounds, ¼ inch thick (see note 1)
- 2 slices thick-cut crusty bread
- 1 ½ teaspoons olive oil, plus more to coat grill
- 2 tablespoons mayonnaise
- ¼ teaspoon garlic powder (see note 2)
- ¼ teaspoon lemon juice
- black pepper, to taste
- hot sauce, to taste (optional)
- tomato slices
- lettuce leaves
Instructions
- Heat a cast-iron grill pan or skillet over medium-high heat. While the grill pan/skillet is pre-heating, continue with the next steps. (If you are not using cast-iron, see note 3.)
- Add the mayonnaise, lemon juice, garlic powder, a pinch of black pepper, and a few dashes hot sauce (optional) to a small bowl. Mix well to combine. Taste the mayo and add more lemon, pepper, and/or hot sauce if desired. Set the mayo aside.
- Pat the halloumi slices dry, then brush both sides of the halloumi and onions slices with oil and sprinkle both sides with black pepper.
- Oil the grill pan or skillet well. Place the halloumi slices, onion slices, and bread slices on the pre-heated grill pan or skillet. If you don't have enough room on your pan and need to cook the ingredients in stages, save the halloumi to cook last.
- Let the ingredients cook, undisturbed, for 2 - 3 minutes, or until nice grill marks appear.
- Flip the ingredients and cook for an additional 2 - 3 minutes. The halloumi should have a soft appearance, and when you touch it with tongs or a spatula, it should have some give to it. Remove the ingredients onto a plate.
- Spread the mayo onto one side of each slice of bread. Layer the halloumi, grilled onions, lettuce and tomato onto the sandwich and serve immediately.
Notes
To make the onion rounds, cut the stem ends off the onion, then peel off the skin. Place the onion on the cutting board so the two cut ends are facing to the sides. Continue to slice the onion in the same direction as you cut off the ends, creating ¼ inch thick rounds. Do not separate the slices into rings; it will be easier to grill the onion in one solid piece. However, it's no problem if the onions do separate a bit when you flip them on the grill.
If you prefer the more powerful flavor of fresh garlic, feel free to substitute ¼ teaspoon crushed garlic for the garlic powder.
Cast-iron is thick and takes several minutes to pre-heat. If you are using a different type of pan, you may not need to pre-heat it as long, depending on the material, so adjust the timing accordingly. If you are going to use a non-stick pan, oil the pan first and only pre-heat it for a minute or two, being sure not to overheat the pan.
If you like, you can also cook the halloumi, bread and onions on an outdoor grill set over medium-high heat (around 375 - 450 degrees F). Be sure to oil the grill grates very well so the halloumi does not stick, and monitor the ingredients well during cooking to make sure they don't burn, since outdoor grills can have hotter and cooler spots.
The nutrition information below is an estimate provided by an online nutrition calculator, and should not be considered a substitute for professional medical, health, or nutritional advice. See our full nutrition disclosure policy.
Nutrition
- Serving Size: 1 sandwich
- Calories: 763
- Sugar: 8 g
- Sodium: 3646 mg
- Fat: 58 g
- Saturated Fat: 22.4 g
- Carbohydrates: 36.6 g
- Fiber: 4.2 g
- Protein: 31.5 g
- Cholesterol: 10 mg
Keywords: halloumi sandwich, halloumi cheese sandwich, easy halloumi sandwich
Helena
This is exactly the recipe I need! I just bought some halloumi cheese and was wondering how to prepare it. You always have the best recipes!
Kate
Aw thank you so much! If you try the recipe I hope you enjoy it 🙂