Slice the onions in half and then peel the paper off. Thinly slice into half moons

Heat the olive oil in a pan with sides on medium low. Add the onions and cover them. They will start to sweat. 

Once they have become translucent, about 5 minutes, add the garlic and a pinch of salt. 

Continue to cook the onions, covered, checking them every so often and stirring them around. 

When they are nice and caramelized and completely buttery and soft, take them off the heat and stir in the mustard. Let cool. 

Make the pie crust. (See recipe on the blog.)

Place the crust on a parchment on a baking sheet and preheat the oven to 350.

Drop the onions onto the middle of the pie crust and spread out leaving about an inch of dough. Then, fold the dough over and create the edge of the crust, folding it over itself to seal it. You can see what that looks like in the photo.

Bake for 35 to 45 minutes until the crust is nicely browned. Let cool for a few minutes and then slice with a pizza cutter. Serve warm (but it is delicious cold too.) Enjoy!