As another attempt to elevate the onion, I offer you, dear reader, this onion tart. I’m not going to lie, it has a ton of steps. But it is the exact thing you want to be eating the next time a chilly fall night rolls around. The onions are caramelized and wonderfully tender. There’s also the sweet knowledge that the protein source in your meal is butter (and egg). Serve with a green salad.
for the filling
4-5 medium onions (i like red onions)
1/2 cup kalamata olives
handful of cherry tomatoes quartered
2 room temperature eggs
2 tablespoons fresh herbs (sage, thyme, or tarragon)
2 tablespoons butter
salt and pepper to taste
for the crust
1 heaping cup all-purpose unbleached flour
1/2 teaspoon salt
dash of sugar
4 tablespoons room temperature butter
3 tablespoons cold water
Combine flour, sugar and salt in a large bowl. Drop the butter onto the flour and mix gently with your hands. If you truly have room temperature butter, this process is quick and easy. Sprinkle some water on top and mix in just until the dough holds together. Form a round and wrap in plastic. Refrigerate dough at least 30 minutes.
While dough is chilling, prepare the filling. Heat the butter over medium heat until just foamy and fragrant, add the onions and herbs, and cook for 2-3 minutes. Turn the burner to low and cook at least 30 minutes stirring occasionally. Add salt and pepper to taste. Toss in the tomatoes and olives, cook briefly, and then put filling into a bowl to cool.
Roll out the tart dough and gently press into tart pan. Then put tart pan with dough into the freezer while the oven preheats. I strongly advise you to reserve some dough for hole patching. Keep it in the refrigerator while the crust cooks. Preheat the oven to 400 degrees. Bake tart shell on a cookie sheet for 25 minutes, until the crust is golden.
Turn the oven down to 375 degrees. Bring out the bowl with the filling, and gently fold in the two eggs. Plug any holes that have formed in the crust, and then fill the tart and place on a cookie sheet in the oven. Cook for 45 minutes, shielding the crust with foil if necessary.
Cool on a rack for 20 minutes.