Apple and Caramelized Onion Tart

A recipe for Apple and Caramelized Onion Tart! A flaky pie crust is filled with caramelized onions and Gruyere cheese, layered with sliced apples, and baked until golden.

Brunch Week

Welcome to the fourth annual #BrunchWeek! We are so excited to have you join us this year as we celebrate Brunch and prepare for Mother’s Day.

Bloggers from around the country will showcase their best brunch dishes, from cocktails to cakes, breakfast breads, tarts, and quiche – there is something for everyone! 

For the second day of #BrunchWeek, I made these Apple and Caramelized Onion Tarts. Check out what else I made this week:

• Macaroni and Cheese Soufflé
• Chocolate Beghrir (Algerian Chocolate Honeycomb Pancakes)
• Teh Tarik (Malaysian Pulled Tea)
• Lemon Blueberry Parfait

Apple and Caramelized Onion Tart

It may be nearly summer, but I am bringing a little fall flavor to #BrunchWeek with these Apple and Caramelized Onion Tarts.

A simple pie crust base is filled with sweet caramelized onions and sage, then topped with shredded Gruyere cheese and thinly sliced apples. They are baked until golden and best served warm or at room temperature. They would make an elegant addition to a Mother’s Day brunch table.

The trick to caramelizing onions is to not rush it. Keep the heat around medium low to slowly bring out the flavor over about 30 minutes.

Sprinkling the apple slices (cut as thinly as possible, about 1/8th of an inch or smaller) with salt and sugar and allowing them to sit for an hour helps release some of the liquid. This keeps them in great condition for arranging over the tops of the tarts and prevents that excess liquid from seeping into the tarts and making them soggy. No need to rinse off the salt and sugar from the apples after they have been resting.

I used 4.75 inch round tart pans with removable bottoms to make smaller tarts in perfect serving sizes. You can also use the ingredients to make one larger 9 inch tart.

Check out what everyone else made:

• Baked Apple Cinnamon Doughnuts by The Chef Next Door
• French Toast with Apple Compote and Caramel Syrup by The Redhead Baker
• Fiddlehead, Sun-Dried Tomato and Basil Quiche by Palatable Pastime
• Poached Eggs on Asparagus Bundled with Prosciutto on Cheesy Polenta by Culinary Adventures with Camilla
• Baked Seafood Stuffed Avocados by Rants From My Crazy Kitchen
• Kielbasa Welsh Rarebit by A Day in the Life on the Farm
• Pulled Pork Pancakes by Ketchup with Linda
• Sausage and Fried Apples by Making Miracles
• Lemon Meringue Angel Food Cake by Love & Confections

Apple and Caramelized Onion Tart Recipe

Pie Crust adapted from Everyday Annie, Apple Topping from Pastry Chef Online, and Tart from Spice Roots

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Apple and Caramelized Onion Tart

A recipe for Apple and Caramelized Onion Tart! A flaky pie crust is filled with caramelized onions and Gruyere cheese, layered with sliced apples, and baked until golden.

Course Side Dish

Cuisine N/A

Keyword apple, apple pie, caramelized onion, onion, pie, tart

Prep Time 20 minutes minutes

Cook Time 1 hour hour 30 minutes minutes

Resting Time: 2 hours hours

Total Time 3 hours hours 50 minutes minutes

Servings 1 (9 inch) Tart

Ingredients

Pie Crust:

• 1 1/4 cups all-purpose flour
• 1 tablespoon granulated sugar
• 1/4 teaspoon salt
• 8 tablespoons unsalted butter chilled and diced
• 2 1/2 tablespoons cold water
• 1/2 tablespoon apple cider vinegar
• Butter for greasing pie pans

Apples:

• 2 apples cored and thinly sliced
• 1/4 teaspoon salt
• 2 tablespoons granulated sugar

Tart:

• 2 tablespoons unsalted butter divided
• 1 tablespoon olive oil
• 1 teaspoon fresh sage leaves thinly sliced
• 3 large onions cut in half and thinly sliced
• 2 eggs
• 1/4 cup heavy cream
• 3/4 cup shredded gruyere

Instructions

To make the pie crust:

• In a large bowl, mix together the flour, sugar, and salt. Cut in the chilled butter using a dough blender, forks, or your fingers until the texture becomes coarse and no pieces are larger than the size of a pea. Mix in the water and vinegar just until a smooth dough forms.
• Flatten the dough into a disc and wrap in plastic. Refrigerate for at least 30 minutes.
• Grease 6 (4.75 inch) tart pans or 1 large tart pan (9 inch) with butter. On a lightly floured surface, roll the dough into a thin circle large enough to cover the bottoms and sides of the 9 inch pan or divide among the 6 (4.75 inch) dishes.
• Transfer to the pans, pressing to cover the bottom and slightly overlap the sides. Prick the bottoms a few times with a fork. Place in the refrigerator for another 30 minutes.
• Preheat oven to 400˚F. Cover each pie crust-lined pan lightly with parchment and fill with ceramic pie weights or uncooked rice. Bake for 10 minutes. Remove from oven and remove the parchment.

To make the apples:

• Place the thinly sliced apples in a colander over a bowl or in the sink. Sprinkle with salt and sugar, then toss to coat. Allow to sit for an hour while preparing the remaining ingredients.

To make the caramelized onion base:

• In a large pot, melt together 2 tablespoons butter and olive oil over medium heat. Add the sage and cook for about a minute to crisp. Mix in the onions and salt. Cook for a minute, then reduce heat to medium low. Cover and cook, stirring occasionally, until golden and caramelized, 30-45 minutes. Transfer the onions to a bowl and allow to cool to room temperature.
• Preheat oven to 425˚F. Mix the eggs and heavy cream into the cooled onions. Divide among the partially baked pie dishes. Top evenly with cheese.
• Arrange a few apple slices flat over the filling around the edge with the peel side facing the crust. This will create a base for layering the remaining apple slices.
• Starting along the edge, layer the apple slices in a circular pattern, alternating the direction if desired and if room is available using the larger tart pan (there wasn't enough space in the 4 inch tart pans). Brush the tops with melted butter and bake in the 425˚F oven until the filling is set and the crust is golden, about 30 minutes (closer to 40-45 minutes for a 9 inch tart). If the edges of the apples are starting to burn, cover lightly with foil and reduce heat to 375˚F.
• Serve warm or at room temperature.