Puff pastry hot dogs with caramelized onions

This time I made the caramelized onions on really low flame, without salt or sugar, just on a little oil. They turned out sweet delicious.

I pre-fried the hot dogs on a little oil

I cut the puff pastry into 4 pieces and added a slice of cheese on each

Then I added 2 tbsp mustard and 2 tbsp ketchup onto each square

Now comes the hot dogs and I nicely packed them and glazed each with some egg yolk

Then they spent some quality time in the oven and I took them out when they were golden. I served them with the caramelized onions