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I absolutely love, love, love fresh garden tomatoes! But – this happens every summer – when our homegrown tomatoes are finally ripe – they ALL get ripe at the same time!
So at this point, we’re still picking about five pounds of tomatoes a day. I’m not really complaining because we’ve been making some of our favorite tomato recipes: sauce, jam, pie, pizza sauce, soup, relish, pizza and salad, plus this quick sauté, and this delicious dinner!
And our latest, favorite recipe to share with you is this Fresh Tomato Au Gratin. Like other au gratins this recipe starts with a delicious creamy sauce that gets layered with chunks of fresh tomatoes and cheese. We also layered in some chopped, fresh basil (from our garden of course) and topped the whole dish with light and crispy panko bread crumbs.
This tomato au gratin bakes up quickly, and its savory, cheesy flavor is sure to be a hit with the whole family! Serve with a fresh garden salad for a delicious, end-of-summer meal.
P.S. Before we share the recipe, I do want to point out one very important step when making this tomato au gratin. Make sure that you remove as much liquid as possible from the tomatoes before baking. Too much juice – and your casserole will end up soggy! We share some tips on how best to drain the tomatoes in the recipe below.
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Fresh Tomato Au Gratin
Ingredients
- 3 pounds Plum-type tomatoes such as Roma, or any large variety, cut into large chunks
- 2 teaspoons salt to help remove water from tomatoes
- 3 tablespoons butter
- 2 cups chopped onions
- 1 tablespoon minced garlic
- 2 tablespoons flour
- 1 1/2 cups heavy cream
- 1/2 teaspoon kosher salt
- 1/4 teaspoon white pepper
- 1/2 teaspoon dry Colman’s mustard
- 1/2 teaspoon freshly grated nutmeg
- Few drops Tobasco sauce
- 1/2 cup basil chopped
- 8 ounces Swiss cheese, shredded and divided
- 1 1/2 cups panko bread crumbs
- 1/2 teaspoon paprika
- 3 tablespoons melted butter
Instructions
- About 4-6 hours before baking (or overnight), place the cut up tomatoes in a colander or strainer over a bowl and sprinkle generously with the salt. Stir to combine. Allow the tomatoes to drain their liquid, stirring occasionally and gently pressing down on the tomatoes (use a large spoon or a small flat bowl to press the tomatoes against the sieve but not too hard that you mash them), until the tomatoes are very well drained. Blot with a paper towel if necessary to remove extra moisture or squeeze in paper towels.
- Preheat oven to 375 degrees.
- In a medium pot, heat butter over medium high heat and sauté onions and garlic for 3 minutes.
- Reduce to medium and add flour and stir frequently for 3 more minutes.
- Microwave cream to hot but not scalding (necessary to avoid lumps). Add this to onion and flour mixture and stir with a whip to combine.
- Add salt, pepper, mustard, nutmeg and Tobasco sauce. Stir and remove from the heat.
- In a 9 inch round, 3 inch deep casserole dish, spray inside with pan spray. Then ladle a small amount of the sauce to coat bottom of pan ( about 1/3 cup).
- Then begin layering half of the tomatoes, half of the remaining sauce, half the cheese, all of the chopped basil, the other half of the tomatoes, the other half of the cheese and the rest of the sauce.
- In a small bowl, mix panko crumbs, butter and paprika and sprinkle on top of casserole.
- Bake uncovered for 30 minutes, then let rest for 15 minutes to set up before serving.
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SO jealous of your tomatoes…I didn’t do a garden this year (shuffles her feet). I have never had tomatoes in this way before, but the ingredient list sings to me!
Thanks Colleen!
This looks truly incredible! I love that crunchy topping and all the cheeeeese!!!! Pinning and can’t wait to try this!
Thank you Renee!
Oh that shot with the melty cheesy just look fabulous! Sounds like the perfect way to use up summer tomatoes.
Thank you Susan!
This looks like the most amazing dinner side! Heck, I’d probably just eat it for dinner as a main course. So yummy!
Thanks Kim!
I could eat this every day, it looks amazing!
Thanks Lauren!
Ooh nice use of late summer tomatoes. Delicious! Great tip on extracting as much liquid as possible from the tomatoes. TY!
Thank you!
This is my kinda au gratin.
Thanks Paula!
This looks delicious! What a great way to use those fresh garden tomatoes…thanks for sharing!
Thanks Jodee!
This looks DIVINE! perfect comfort food
Thanks Claire!
I have 3 cherry tomato plants in my garden (and living in CA, allows the growing season to keep on going. Yay me!). Nature’s candy. Absolutely love everything about this gratin!
Thanks Amy!