Spring Onion Tart with Puff Pastry Crust

"We would load up the yellow Cutlass Supreme station wagon and pick blackberries during blackberry season, or spring onions during spring onion season.  For us, food was part of the fabric of our day."

~Mario Batali

Sharing recipes that cause excitement around here is the reason I started this blog. You might be thinking, "spring onion tart - ho hum." Not so fast.  This is something I've thought about and been meaning to try for years.  When I served it to The Mister last night, after taking a bite, he exclaimed (with his mouth half-full, btw) "I am the luckiest man alive!"  (He is so much fun to cook for.) High praise for the humble onion tart.  It's just one of those things.  Sometimes simple is best.  


The smell of the onions slowly cooking with fresh thyme....oh boy...it really primes the appetite.  Even if you're not a fan of raw onion, you might like this.  The slow cooking takes the bite out and leaves you a creamy, savory filling.   It's good warm or at room temperature, and although we had it as part of a light dinner served with soup and salad, you could shape it as a rectangle on a cookie sheet, cut the tart into small squares and it would make a nice appetizer that would be elegant dressed up with a pinch of microgreens on each square.  I'm considering this for Easter.


I've seen enough onion tarts over the years to know the basic fillings and variations.  For mine, I started with 1/4 of  my favorite Fanny Farmer base quiche binder, and then added the spring onion filling. The puff pastry was a no-brainer for it's ease of preparation and the crispy, buttery results.  

Cooks notes: Pre-baking of the crust is important, so that it's crispy.  That really makes it. If you skip that step the bottom will be soggy and it may become misshapen as it bakes.  Take care to cook the onions very slowly on low.  You're goal is not to brown them, but to soften and very slightly caramelize them.  Adding the garlic at the very end is important because you just want to warm it up and bring out the fragrance.  If it browns it will be bitter.  Fresh thyme is best, but if you have to use dried, use very little, just a pinch, because the dried is much stronger and you don't want it to overpower.

Spring Onion Tart with Puff Pastry Crust
Serves 4


1 sheet puff pastry, thawed (I prefer Pepperidge Farm)
2 tablespoons olive oil
2 tablespoons butter
2 medium onions, peeled and thinly sliced (Vidalia are best, but white is fine)
2 bunches spring onions (scallions) about 12-14
2 cloves garlic, peeled and minced
1/2 teaspoon sea salt
1/2 teaspoon fresh ground black pepper
1/2 cup heavy cream
1 egg
1 cup shredded Swiss cheese (good stuff, not pre-shredded, bagged)
2 tablespoons grated Parmesan cheese


Preheat oven to 375 degrees.  Butter tart pan.  Roll thawed sheet of  puff pastry to stretch it a bit to fit your tart pan, if necessary.  Pinch pastry up the sides of pan.  Cut away any pasty that overhangs.  Poke bottom of crust with a fork.  Cut a piece of foil or parchment paper that is bigger than your pan.   Lay this over the puff pastry crust, allowing plenty of overhang.   Fill with baking weights, dried beans or rice to weigh it down.  Bake for 25-30 mins.  Remove weights and cool.




Cut root end of scallions off, then slice from the white end, about 2/3 a way up the green part.  Discard the last 1/3 of the green part.  Set aside half of the greenest part of the sliced scallions.  The rest, place with your sliced onions.


In a large preferably nonstick saucepan, melt butter together with the olive oil on low-medium heat.  Add the sliced onions and scallions (except for the green ones you set aside).  Add salt, pepper and thyme.  Allow them to come to a very low simmer, stirring occasionally, and cook for about 15-20 minutes until they are very soft, and even slightly caramelized, but not browned.  Add garlic and cook for about 3 minutes more, stirring.  Set aside until mostly cooled off.  


In a medium bowl, whisk egg, stir in cream and shredded Swiss cheese.  Stir in the cooled cooked onion mixture and pour into the cooled crust, spreading evenly.  Sprinkle the reserved green part of the scallions evenly over the filling and press them down lightly.  Sprinkle the Parmesan cheese over the filling.


Bake for 20-25 minutes or until filling is set and golden.  Cool for 5 minutes.  Serve hot, warm or at room temperature.