Preheat your oven according to the instructions on the puff pastry shell package.
Bake the puff pastry shells as directed until they are golden brown and puffed. Once done, remove them from the oven and let them cool.
Caramelize Onions
Heat olive oil in a large skillet over medium-low heat.
Add thinly sliced onions to the skillet and cook, stirring occasionally, until the onions are soft and caramelized, about 25-30 minutes.
Once onions are a deep golden brown, remove from heat and set aside.
Prepare Goat Cheese Filling
In a bowl, combine crumbled goat cheese and fresh thyme leaves. Mix well.
Assemble Tartlets
Once the puff pastry shells have cooled, use a fork to carefully remove the tops.
Fill each shell with a spoonful of the caramelized onions, followed by a generous amount of the goat cheese and thyme mixture.
Bake
Preheat your oven to 375°F.
Place the filled tartlets on a baking sheet.
In a small bowl, beat the egg to create an egg wash. Brush the egg wash over the edges of the puff pastry to give them a golden color.
Bake in the preheated oven for about 15-20 minutes or until the edges are golden brown.
Allow the tartlets to cool for a few minutes before serving.
Notes
1. Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed. The nutritional value will vary based on the type and amounts of ingredients used. It does not include the nutrition for any substitutions or additions.2. Be sure to check out the Key Ingredients along with the Recipe Tips and Notes sections found in the post, for more tips, options, substitutions, and variations for this recipe! You will also find step-by-step photos.