
It’s almost tomato season here in Illinois, which means my mom is about to have more tomatoes than she knows what to do with.
This seems to happen every year towards the end of the summer. My moms tomato plants suddenly pop and shes over flowing with tomatoes. More than she knows what to do with!
Last year she was trying to come up with every recipe in the book to use them all up. She made tomato tarts, soup, sauce, and the list goes on!

So, in preparation for the inevitable, I thought why not come up with a low carb tomato recipe that I make with all these tomatoes!
That’s why this low carb Tomato Gratin was born!
Tomato Gratin is a side dish that is slightly higher in carbs. I would say this serves 4 people and based on My Fitness Pal calculations, that comes out to 4.7 net carbs, so for those Keto people out there, this is something to keep in mind!
I think Tomato Gratin is the perfect addition to any summer meal. And a great way to use up all those tomatoes!
I hope you love this low carb Tomato Gratin with caramelized onions as much as we do


Tomato Gratin
Ingredients
- 4 Roma Tomatoes
- 1 Large Sweet Onion
- 1 Clove Garlic Minced
- 1/4 Cup Parmesan Cheese Grated
- 1/4 Cup Whisps Or other parmesan cracker
- 1 Tbsp Olive Oil
- Salt and Pepper
Instructions
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Thinly slice Roma tomatoes. Once sliced, lay them out on paper towels and sprinkle with salt. Top with another sheet of paper towels. This helps to get out the moisture and keeps your dish from being soggy. Allow the tomatoes to sit for 1 hour.
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In the meantime, place whisps in a plastic bag and crush using a mallet or rolling pin.
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Preheat oven to 450 degrees.
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In a medium pan over medium heat, add olive oil. Once hot, add the onions and cook until caramelized. Cook for 10-15 minutes until golden brown. Be careful not to let the pan get too hot, otherwise the onions will char rather than caramelize.
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Add garlic and cook until fragrant, about another minute.
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Place onion and garlic mixture on the bottom of an 8×8 baking dish in a thin, single layer.
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Next, layer the tomatoes on top, as pictured.
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Place in the oven and bake for 15 minutes.
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Remove the dish from the oven and top with parmesan and crushed whisps.
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Return to the oven and cook another 5-10 minutes until cheese is melted.
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Remove from the oven and serve!
