This tart celebrates the sweetness and caramelized goodness of three kinds of onions nestled in a buttery crust. With minimal prep time and cooking, you can indulge in the comforting taste of this savory treat in no time. The medley of onion varieties dances on your taste buds, while the flaky crust provides the perfect canvas for this mouthwatering delight. Let’s begin!

Instructions

Preheat your oven to 375°F (190°C).
To make the butter crust, in a food processor, combine the all-purpose flour, cold cubed butter, and salt. Pulse until the mixture resembles coarse crumbs. Slowly add ice water, one tablespoon at a time, and pulse until the dough comes together. Form the dough into a disk, wrap it in plastic wrap, and refrigerate for 10 minutes.
While the dough chills, prepare the onion filling. In a large skillet, heat the olive oil over medium heat. Add the thinly sliced yellow onions, sweet onion, and shallots. Cook for about 8-10 minutes until the onions are soft and translucent. Stir in the balsamic vinegar, granulated sugar, salt, and black pepper. Continue to cook for an additional 5 minutes until the onions caramelize slightly. Remove from heat and let it cool.
Roll out the chilled dough on a floured surface to fit your tart pan. Gently press the dough into the pan, trimming any excess.
Spread the caramelized onion filling evenly over the crust. Sprinkle the grated Gruyere cheese on top.
Bake the Onion Tart in the preheated oven for 15-18 minutes until the crust is golden brown and the cheese is bubbly and melted.
Garnish with fresh herbs as desired.

Notes

You can use a mix of sweet and red onions for a well-rounded flavor profile. To enhance the taste, sprinkle some crumbled bacon or toasted pine nuts on top before serving. Serve this dish with a fresh green salad or roasted veggies for a delightful dinner. This tart is delicious when warm, but it also tastes fantastic at room temperature, making it a versatile dish for potlucks and gatherings. Enjoy!

*Please keep in mind that the following nutritional information is based on estimates and can vary depending on the specific brands and ingredients used.