Mushroom and Asparagus Tarts

This month's Bon Appetit was really fabulous. I made a vow to work more with puff pasty, and voila! They had the most delicious looking recipe. I made a few tweaks based on what I had in the fridge, but it was a really tasty spring treat.

Mushroom and Asparagus Tarts

2 sheets frozen puff pasty, thawed
1/4 cup butter
2 cloves garlic, minced
1 leek, rinsed and sliced
12 ounces baby portabello mushrooms
Salt and pepper to taste
1 pound asparagus spears, cut on diagonal into 1-inch pieces
Zest from 1 lemon
1 cup shredded Gruyere cheese

Roll out pastry sheets and cut into 6 squares each and place on a baking sheet. Melt butter in a large skillet over medium heat. Add garlic and leeks and saute 2 minutes. Add mushrooms and salt and pepper and cook additional 3 to 5 minutes. Place mushroom mixture in a bowl and refrigerate about 15 minutes. Toss in asparagus spears, lemon and cheese.

Heat oven to 400 degrees. Place mushroom asparagus mixture on each pastry square, leaving a 1/2 inch border on each. Bake tarts 20 to 22 minutes, rotating halfway through cooking time.