French Onion & Blue Cheese Tart

Directions

1. Start by cooking the onions. They need to be cooked slowly on low heat, so it’s best to begin with those. Melt the butter in a large nonstick frying pan—we have a load of onions to cook. When the butter has melted, pick off the thyme leaves and add, then add the garlic and onions. Mix everything together. Now add the pepper, salt, and sugar and mix. Cook on medium heat for 30 minutes, stirring occasionally, until you have onions that look like the kind you would only eat with a burger in a Sunday market at 6 a.m.!
2. While that cooks, start on the pastry. Heat the oven to 400°F. Line a baking sheet with some parchment paper or use the paper the pastry comes in and roll out the pastry onto the sheet.
3. Using a knife, score a smaller rectangle ½ inch/1 centimeter inside the pastry rectangle, making sure not to cut all the way through. Pierce the inner rectangle with a fork all over to allow the steam to escape when it bakes.
4. Brush the edges with the egg and bake for 20 minutes, until golden all over.
5. Take out and, using the back of a spoon, push down all the puffed-up pastry of the inner rectangle, creating a nice neat border.
6. Take the blue cheese and crumble all over the inner rectangle of the pastry. Add the onions and scatter them all over till you have an even layer. Now bake for 15 minutes.
7. Take out and let cool for 10 minutes before eating, sprinkled with the chives.