Low Carb Onion Buns

Each of these low carb onion buns has 4 grams of net carbs (7.2 g carbs minus 3.2 g fiber), plus 12.9 grams of protein and 324 calories, according to our recipe card. They’re made with an almond flour and mozzarella “fathead” dough instead of wheat flour, and a batch of 4 buns is ready in 30 minutes. They’re sturdy enough to hold a burger and soft enough to actually enjoy.

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I LOVE to bake; Have since I was a little girl. Baking is therapeutic and right now, with Addie getting her 2 year molars, I need all the therapy I can get! Needless to say I’ve been baking up a storm.

Zoey and I made some delicious organic raspberry apple cinnamon muffins and a loaf of organic whole wheat bread. The beautiful scents that were wafting through my house were driving me bonkers! Who doesn’t audibly sigh at the scent of fresh bread?

To make up for it, I decided to bake some yummy low carb buns to go with the burgers I made for dinner. My mom used to make these incredible onion buns, so I made a low carb version… YUM!!

These go great with burgers or any kind of sandwich you want! I also love to dip them in soup. They are basically magic. I hope you love these low carb buns as much as I do!

Why this recipe works

1. Burger buns loaded with all sorts of oniony goodness? That alone is why this recipe works so, so well.
2. These low carb buns not only have great flavour, they hold up super well so are perfect for any sort of burger or sandwich.
3. They are ready in no time! I love how fast I can toss a batch together, especially when I lose track of time.

Low Carb Onion Bun Ingredients

These low carb buns are a variation of the fathead dough. I use a similar dough for my Everything Bagels and Fathead Pizza Crust. This is what you’ll need:

• butter
• onion
• almond flour (blanched, super-fine)
• baking powder
• baking soda
• onion powder
• dehydrated onion flakes (dried minced onion)
• sea salt
• mozzarella
• cream cheese
• eggs
• white vinegar

How to make Low Carb Buns

These low carb buns are super easy to make. Here’s how:

Start by heating the oven to 375°F. Heat a skillet on medium high heat with some butter. Mince the onion and once the butter is ready, fry the onion until it begins to brown. Remove from the heat and set aside.

Grab a medium sized microwave safe bowl and toss in almond flour, baking powder, baking soda, onion powder, onion flakes and sea salt. Whisk well then toss in mozzarella cheese until evenly mixed.

Plunk cubes of cream cheese on top of the mixture and microwave for 1 minute. Mix with a wooden spoon, then microwave for an additional 30 seconds. Mix again, and if the mozzarella is not fully melted, microwave in 15 second intervals until it is.

Fold in 1 full egg and 1 egg white and once fully combined, mix in the vinegar just until it’s incorporated. Don’t overwork it: the vinegar reacts with the baking soda right away, and kneading the dough too much at this point keeps the buns from rising, so they come out small and hard.

Divide into four and shape each piece into a bun about the size of a little hockey puck. They spread quite a bit while baking, so be sure not to form them too large. Place evenly on a baking sheet lined with a non stick baking mat or parchment paper, then brush the tops with the cooked onion/butter.

Bake for 14-16 minutes, until the tops of the buns have browned. Cool for a couple of minutes before using as you like!

Watch it all go down!

Expert Tips

1. Mince the onion fairly small so that there aren’t huge chunks of onion on top of your buns.
2. Once the vinegar hits, the dough will instantly start to puff up a little bit. Be gentle while shaping the buns to keep the most volume possible.
3. This recipe can easily be doubled or tripled if you are having lots of company over, or if you want to make a large batch to freeze.

How to store Low Carb Buns

Although these Low Carb Onion Buns are best when eaten fresh, they keep well for quite a while if stored properly. Once cool, refrigerate them in an airtight container and eat them within 3 to 4 days, the USDA guideline for cooked leftovers.

Want them to last longer? Toss them into a freezer safe container or ziploc and freeze them. For the best texture and flavor, use them within 3 to 4 months; they stay safe longer, but they slowly dry out. They take no time to thaw, so I often throw them into the freezer right away.

Need some inspiration?

There are a lot of delicious burgers and sandwiches you can make with these yummy low carb buns. Here are a few ideas:

• Crispy Chicken Burgers
• Ham and swiss cheese with Keto Honey Mustard
• Prosciutto Bocconcini Stuffed Burgers
• Tuna sandwiches, or a Keto Tuna Melt
• Low Carb Turkey Burgers
• Beef Dip
• Instant Pot Pulled Pork
• Grilled Keto Burgers

Love this recipe? Try these other low carb recipes next:

90 Second Keto Bread

Biscuits with Cheddar

Tomato Basil Flatbread

Hot Dog Buns

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Michelle Beaupre & Mitch Durfee

Low Carb Onion Buns

5 from 6 votes

These onion packed low carb buns are super quick and easy to throw together for some extra delicious keto burgers or low carb sandwiches.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 15 minutes mins

Total Time 30 minutes mins

Servings: 4 buns

Course: Main Course

Cuisine: Canadian, Low Carb

Calories: 324

Ingredients Method Video Notes

Ingredients

  

• 2 tbsp butter
• 2 tbsp minced onion
• 1 cup almond flour
• 2 tsp baking powder
• ¼ tsp baking soda
• ½ tsp onion powder
• ½ tsp onion flakes
• ¼ tsp sea salt
• ¾ cup mozzarella cheese
• 2 tbsp cream cheese
• 1 egg
• 1 egg white
• 1 tsp white vinegar

Method

 

Equipment Needed

1. 1 x Baking Sheet and Non Stick Baking Mat

   or Parchment Paper
2. Skillet
3. Medium Sized Microwave Safe Bowl
4. Wooden Spoon
5. Olive Oil Spray

Directions

1. Heat oven to 375°F and line a baking sheet with a non stick baking mat or parchment paper. Heat a skillet on medium high and add the butter. Once hot, fry the minced onion until it begins to brown, then remove from heat and set aside.
2. Combine almond flour, baking powder, baking soda, onion powder, onion flakes and sea salt in a medium sized microwave safe bowl and mix well. Toss in shredded mozzarella, then place the cream cheese on top. Microwave for 1 minute. Mix with a wooden spoon, then microwave for an additional 30 seconds.
3. Mix again, and if the mozzarella is not fully melted, microwave in 15 second intervals until it is. Fold in 1 egg and 1 egg white and once fully combined, mix in the vinegar just until incorporated. *see notes
4. Divide into four and form into buns, see photos and video above for correct shape. They will spread while baking so be sure not to form them too large. Place evenly on a baking sheet with a non stick baking mat, then brush the tops with the cooked onion/butter. Bake for 14-16 minutes, until the tops of the buns have browned.

Video

Notes

Expert Tips

1. Mince the onion fairly small so that there aren’t huge chunks of onion on top of your buns.
2. Once the vinegar hits, the dough will instantly start to puff up a little bit. Be gentle while shaping the buns to keep the most volume possible.
3. Shaping the buns: they will spread quite a bit during baking so you want to make sure they aren’t formed too large. I tend to make mine in the shape of little hockey pucks. See the process photos above or the video for reference.
4. This recipe can easily be doubled or tripled if you are having lots of company over, or if you want to make a large batch to freeze.

Nutrition Facts

Nutrition facts are an estimate only! The ingredients you choose could have different nutritional values than the ingredients I have used.  

Deduct fibre from the total carbs to get 4 g net carbs per bun.

Frequently Asked Questions

How many net carbs are in low carb onion buns?

Each bun has 4 grams of net carbs: 7.2 grams of total carbs minus 3.2 grams of fiber, according to our recipe card. That makes them a solid swap for regular burger or sandwich buns on a low carb diet.

How long do these buns take to make?

About 30 minutes total, including 15 minutes of prep and 15 minutes to bake.

How do I store low carb onion buns?

Once cooled, refrigerate them in an airtight container for 3 to 4 days, or freeze them and use within 3 to 4 months for the best quality, following USDA guidance for cooked leftovers. They thaw quickly, so they’re easy to pull from the freezer as needed.

How many calories are in a low carb onion bun?

Each bun has 324 calories, with 28 grams of fat, 12.9 grams of protein and 4 grams of net carbs, according to our recipe card. The recipe makes 4 buns.

Why didn’t my onion buns rise?

Usually the dough was worked too much after the vinegar went in. The vinegar reacts with the baking soda right away, so mix it in just until it’s combined and shape the buns gently. Also shape them like little hockey pucks rather than flat patties; they spread as they bake.

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