Truffled Potato and Mushroom Tart
- Total Time: 1 hour
- Yield: 4-6 1x
Description
Creamy, cheesy mashed potatoes, crispy, buttery filo dough, earthy, hearty mushrooms, fresh chives, and a drizzle of truffle oil. Are you hungry yet?
Ingredients
- 1 1/4 lb. (565 g) (a little more or a little less if just fine) of russet potatoes, peeled and cubed
- 3-4 medium portobello mushroom caps, thinly sliced
- 5-6 sheets of filo dough
- 1/2 stick of butter, melted
- 3/4 cup (180 ml) white cheddar cheese, grated
- 3/4 cup (180 ml) Gruyere cheese, grated
- 3 large eggs
- 1 cup (240 ml) heavy cream
- salt & pepper to taste
- 2 tbsp (30 ml) minced chives
- truffle oil for garnish
Instructions
- Place cut potatoes in a pot filled with cold water and boil until fork tender, about 15 minutes. Drain.
- Preheat your oven to 375 degrees F. Take whatever dish you are planning on using, I actually used a 8 X 8 in cake pan that I lined with parchment paper (but you can using a baking dish, or a tart pan as well) and brush with melted butter to coat.
- Take one sheet of your filo dough (keep the rest covered with a slightly damp paper towel so it doesn’t dry out) and gently line your pan. Brush melted butter all over the filo, and repeat with 5-6 sheets of dough. You can leave the edges of the filo draped over the sides of the dish for now. Cover with a damp towel or paper towel and set aside.
- In a small bowl beat the eggs together with the cream with a fork. In a large bowl, break up the potatoes with a masher, then add the cheeses and mash until combined. Add the cream and egg mixture and mash and mix until smooth. Season generously with salt and pepper.
- Pour potato mixture into filo-lined baking dish leaving at least 1/2 inch room from the top of the dish. Spread into an even layer and top with your sliced mushrooms. Sprinkle with a little extra ground black pepper and the chives. Gather the extra filo dough that was draped over the edge and crimp it together around the edge of the potato mixture. Brush more butter all over the filo crust, and bake for 20-30 minutes until middle has set and the filo is golden brown. The time will vary depending on the size and depth of your baking dish. Mine took a bit longer since it was so deep.
- Let the tart set up for at least 15 minutes before cutting. Drizzle with a bit of truffle oil and sprinkle with fresh chives before serving.
- Prep Time: 30 mins
- Cook Time: 30 mins
- Category: Main Course
- Cuisine: French
Nutrition
- Serving Size: 1 serving
- Calories: 480
If You Liked This Recipe, You’ll Love These
- Fluffy Mashed Potato and Cheese Pancakes
- Spinach Ricotta Tart
- Rustic Italian Meatball and Potato Soup
- Tartiflette au Reblochon: The French Alpine Potato Gratin
Frequently Asked Questions
Why do I need to keep the unused filo dough covered with a damp towel?
Filo dough dries out and becomes brittle very quickly when exposed to air. The instructions specify covering unused sheets with a slightly damp paper towel so they stay pliable and don’t crack when you layer them into the pan.
Can I use a different pan shape than the 8×8 cake pan?
Yes — the recipe notes you can use a baking dish or a tart pan as well. Just be aware that a shallower dish will bake faster than the 8×8 pan used here, which ran toward the longer end of the 20–30 minute bake window because of its depth.
Why let the tart rest for 15 minutes before cutting?
The recipe specifically calls for at least 15 minutes of resting time so the creamy potato custard — made from 3 eggs, 1 cup heavy cream, and two melted cheeses — can set up and hold its shape when sliced rather than running out of the filo shell. 
How much truffle oil should I use as a garnish?
The recipe calls for “a bit” of truffle oil drizzled right before serving. Truffle oil is potent, so a light hand — a teaspoon or less across the whole tart — is enough to add aroma without overwhelming the Gruyere and white cheddar filling.
