Tomato + Caramelized Onion Tart

I have made a few different versions of this tart. Sometimes I leave out the onions, sometimes I use goat cheese and once made it in a home made pie crust. Every time it’s delicious. Pretty sure you can’t go wrong with any of these ingredients.

Unfortunately we don’t have any tomatoes in our garden yet, so I succumbed to buying Heirlooms at the market. That just means I will have to make it again in the summer, right?


This tart accompanied many other amazing dishes at our Easter brunch. But it can be a stand alone with a salad on the side. Serves about 4 as a meal, 6 as a side dish.



4 medium Heirloom tomatoes, sliced 1/4 inch thick

1 medium sweet onion, sliced.

1 Tbs. butter

2 Tbs. white wine

1 tsp Thyme

1 sheet puff pastry

Boursin cheese, as much as you want

Shredded or shaved parmesan

Basil, torn or cut

Kosher salt

Olive oil



If the puff pastry is frozen, lay it on the counter until soft to the touch, about 30 -40 minutes. Or defrost in refrigerator over night.

Layer a large plate or cutting board with paper towels. Lay tomato slices on a single layer on the prepared plate. Sprinkle with kosher salt, flip them over and repeat. Let them hang out and drain while preparing the onions.

Heat the butter and a tablespoon of olive oil over medium heat, add onions. Saute them for a few minutes and then add wine and thyme. Lower the heat and let them cook until golden brown, stirring every so often. About 20 minutes.

Heat oven to 425. Unfold puff pastry sheet on baking pan, lined with parchment or foil if that’s all you have. With a sharp knife lightly score a border (3/4 inch from the edge) around the entire pastry.

Spread on as much Boursin cheese as you want inside the border and then sprinkle with parmesan. Add the onions on top of cheese when they are good and caramelized. Add your tomatoes, overlapping if necessary. Sprinkle with salt, drizzle with olive oil, add more parmesan if you want and pop it into the oven for about 20-25 minutes or when the pastry is golden brown. Sprinkle with your basil and you are set to serve. Prepare to wow your guests!