Mandarin Orange Dessert: Posset Tart with Whole Wheat Crust

It’s still winter, so it’s still citrus season. These bright and zesty fruits bring some fresh joy to dark days, especially mandarin oranges – one of my favorites. If you are looking for a simple yet flavorful treat that highlights the tart sweetness of citrus, this posset tart is for you. It’s a mandarin orange dessert, perfect for making ahead and storing in the fridge.

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Orange isn’t one of my favorite flavors. In fact, I have avoided drinking orange juice, or eating standard navel oranges as snacks since I was young. But there was always comfort in those cans of mandarin oranges. Little wedges of sweet citrus goodness suspended in a sticky syrup. I knew I wanted this tart to capture that memory.

I decided to elevate it from the canned snack of my youth by using it in a creamy posset tart. Posset is a type of custard that sets up without needing to be baked, because it lacks eggs. That makes for a lighter filling, perfect for delicate citrus flavors. The whole wheat crust pulls it all together.

What You Need to Get Started

You can easily find all of the ingredients for this mandarin orange tart at your grocery store. You can also order online using Amazon Fresh for grocery delivery.

• Pantry: White whole wheat flour, Brown sugar, Sugar
• Spice Rack: Salt, Almond extract
• Fridge: Butter, Lemon juice, Heavy cream
• Produce: Mandarin oranges (zest and juice)
• Equipment: Mixing bowls, Pastry blender, Tart pan, Aluminum foil, Pie weights or equivalent, Microplane zester, Saucepan

How to Make Whole Wheat Tart Crust

Making this mandarin orange tart is a two-step process. You can do it all in one day, or you can make the crust a little bit in advance. However, the entire tart will need to chill at least six hours, or preferably overnight. So be sure to plan ahead.

Let’s start with the crust. A tart crust isn’t all that different from a pie crust, but they do tend to add a little bit of sweetness to the standard butter, flour, salt, and water combo. As an extra bonus, this one doesn’t need to be rolled out, but is instead pressed into the tart pan.

To get started, preheat your oven. Then combine the flour, brown sugar, and salt in a medium mixing bowl. I like using white whole wheat flour because it’s made from the whole grain, but has a softer and lighter texture than standard whole wheat. Whisk these together until they are combined and there are no big lumps of brown sugar.

Then add in the butter, which should be fridge-cold and cut into cubes. To mix this into the flour, use one of my favorite kitchen tools — a pastry blender. The dull metal blades help to cut in the butter, and create little pockets of fat that between flour. That’s what makes the crust nice and flaky.

Once there are no large butter chunks bigger than a pea, and the entire mixture has the texture of wet sand, you can begin adding in cold water, a little bit at a time. At this point, switch to mixing with your hands, but work quickly so the dough doesn’t warm up too much.

Work the water into the flour mixture until it forms into a sticky ball of dough. Then, transfer that into your tart pan. A true tart pan has a removable bottom, so be sure it’s placed on a sturdy surface while you press the crust into it. Use your fingertips to work it into the edges and up the sides, following the natural shape of the pan.

Now we are going to do what is called blind baking. This is when you cover the crust and bake it on its own, with no filling. Since our filling here doesn’t need to be baked at all, we are going to completely cook the crust on its own. Cover it with aluminum foil, gently pressing it along the shape of the crust, into all the corners.

Then pour in pie weights, which are ceramic or metal balls that are heavy enough to keep your crust from rising in the oven. If you don’t have traditional pie weights, you can use dried beans. Or you can even use a different pan on top.

It’s okay to improvise, just be sure you are applying weight evenly across the tart crust. Bake it for twenty minutes covered and weighted down. Then remove all of that and continue baking for an additional ten minutes or so until it’s golden brown, especially at the edges.

Let’s Make a Tasty Mandarin Orange Dessert

Set the crust aside to cool completely while you prepare the filling. This posset custard uses both the zest and juice of mandarin oranges, so get started by grabbing your microplane zester and grating the peel of a couple medium-sized fresh mandarin oranges.

If you can’t find these (they tend to be seasonal), you can use clementines as a replacement. Actually, you can make a posset with nearly any type of citrus, so feel free to experiment with lemons, limes, oranges, grapefruits or any of your favorites.

Once zested, cut the orange in half, and use a citrus press or spoon to get out all of the juice. Be sure that you pour it through a strainer to remove any pulp. But usually, mandarin oranges have very few, if any, seeds.

You will use another mandarin orange later for garnishing, but don’t worry about that for now. Instead, move over to the stove to begin making the posset. This is a very simple custard made from heated cream and sugar, so let’s start there.

In your medium saucepan, combine the heavy cream and sugar and bring it up to a simmer, while stirring to dissolve the sugar. Allow the mixture to continue simmering for a few minutes, stirring frequently. You should notice it thicken slightly, but not too much.

Turn off the heat and then add in the mandarin orange juice and zest, plus a little bit of lemon juice to add some extra acidity, and a dash of almond extract for additional depth of flavor. If you’re not a fan of almond, leave it out, or try with vanilla extract instead. Stir everything together.

While stirring, you will start to believe that this custard made almost entirely from liquids may set up yet. You can feel it begin to thicken slightly as the ingredients come together. Once combined, let the mixture cool for about five minutes, until you can easily handle it.

I like to transfer the custard from the saucepan into a heatproof measuring cup with a spout, for a little bit more control. However, you can skip it if you are confident in your pouring abilities. Pour the posset directly into the cooled crust, still in the tart pan, resting on a plate.

It should come nearly to the top, so go slowly at the end. If a little bit overflows the crust into the tart pan, it won’t really hurt anything other than the presentation. However, if you notice it getting close to a low point in one of the ruffled edges, feel free to stop. You can always chill extra posset in a small glass dish and eat it on its own.

Carefully place the plate with the tart into the fridge and let the entire thing chill for at least six hours. Mine was set at this point, but it was even better the next day when I let it solidify overnight. To check for doneness, pierce the tart with a butter knife. The hole formed should remain and not fill in with posset.

Grab that extra mandarin orange, peel it, and carefully break into its natural wedges. These oranges are super easy to peel — just create a small starting point with your thumbnail, and then use your hands to remove the rest of the skin. Break the wedges apart from the top or bottom, removing the thick center pith.

Garnish as desired. You can even use more than one orange for decorating if you’d like. I went with a simple design on the entire tart, but then decided to serve individual slices with their own fresh wedges as well.

How to Serve a Mandarin Orange Tart

Once this tart is set, you can slice and serve it immediately. Or you can store it in the fridge for a couple days, sliced or unsliced. It’s a very forgiving dessert to make in advance. You can even make and store the unfilled crust for a few days first, for more flexibility.

This fresh, creamy, and citrus treat is a perfect dessert, but don’t let that stop you from enjoying it for breakfast or a mid-afternoon snack as well. I would love to feature this on a brunch table, served with spicy palomas and savory chorizo-spiced flatbreads. Or for less heat, try brûléed brown derby cocktails.

If you are set on dessert, pair this with a cozy winter beverage like a chai white hot chocolate or a more refreshing key lime vodka sour. Or simply let it stand on its own with a mug of orange pekoe tea.

Use Up Leftover Ingredients

• Mandarin oranges make a great snack on their own. Because they are easy to peel and break into pieces, they are perfect to throw in a lunchbox.
• I love using white whole wheat flour, and it’s part of what makes my brown butter banana bread so chewy and moist.
• When it comes to heavy cream, I always say make ice cream! Try some fun and fresh strawberry sundaes.
• Almond extract is one of my favorite secret ingredients. Try adding a dash to the dough for mini skillet cookies.

Special Equipment

• Mixing bowls
• Pastry blender
• Tart pan
• Aluminum foil
• Pie weights or equivalent
• Microplane zester
• Saucepan

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• Wooden trivet
• Orange striped towel
• Small plate
• Tiny pinch bowl
• Beaker measuring cup
• Pyrex measuring cup